【复习指导】2020-2021学年高一信息科技下学期期中重点试题

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2020-2021学年北京市海淀区高一(下)期中数学试卷

2020-2021学年北京市海淀区高一(下)期中数学试卷

2020-2021学年北京市海淀区高一(下)期中数学试卷试题数:19,总分:1001.(单选题,4分)若角α的终边经过点P (-2,3),则tanα=( ) A. −23 B. 23 C. −32 D. 322.(单选题,4分)已知向量 a ⃗ =(1,2),则| a ⃗ |=( ) A.3 B. √3 C.5 D. √53.(单选题,4分) MB ⃗⃗⃗⃗⃗⃗⃗−BA ⃗⃗⃗⃗⃗⃗+BO ⃗⃗⃗⃗⃗⃗+OM ⃗⃗⃗⃗⃗⃗⃗ =( ) A. AB ⃗⃗⃗⃗⃗⃗ B. BA ⃗⃗⃗⃗⃗⃗ C. MB ⃗⃗⃗⃗⃗⃗⃗ D. BM ⃗⃗⃗⃗⃗⃗⃗4.(单选题,4分)在△ABC 中,A 为钝角,则点P (cosA ,tanB )( ) A.在第一象限 B.在第二象限 C.在第三象限 D.在第四象限5.(单选题,4分)下列函数中,周期为π且在区间( π2 ,π)上单调递增的是( ) A.y=cos2x B.y=sin2x C. y =cos 12x D. y =sin 12x6.(单选题,4分)对函数y=sinx的图象分别作以下变换:① 向左平移π4个单位,再将每个点的横坐标缩短为原来的13(纵坐标不变);② 向左平移π12个单位,再将每个点的横坐标缩短为原来的13(纵坐标不变)③ 将每个点的横坐标缩短为原来的13(纵坐标不变),再向左平移π4个单位④ 将每个点的横坐标缩短为原来的13(纵坐标不变),再向左平移π12个单位其中能得到函数y=sin(3x+π4)的图象的是()A. ① ③B. ② ③C. ① ④D. ② ④7.(单选题,4分)如图,已知向量a⃗,b⃗⃗,c⃗,d⃗,e⃗的起点相同,则c⃗ + d⃗ - e⃗ =()A.- b⃗⃗B. b⃗⃗C.-6 a⃗ + b⃗⃗D.6 a⃗ - b⃗⃗8.(单选题,4分)已知函数f(x)=2sin(ωx+φ)(ω>0,|φ|<π2)的图象如图所示,则ω的值为()A.2B.1C. 12D. 149.(单选题,4分)“sinα=cosβ”是“ α+β=π2+2kπ(k∈Z)”的()A.充分而不必要条件B.必要而不充分条件C.充分必要条件D.既不充分也不必要条件10.(单选题,4分)已知函数f (x )=(x-1)3.Q 是f (x )的图象上一点,若在f (x )的图象上存在不同的两点M ,N ,使得 OM ⃗⃗⃗⃗⃗⃗⃗=2OQ ⃗⃗⃗⃗⃗⃗⃗−ON ⃗⃗⃗⃗⃗⃗⃗ 成立,其中O 是坐标原点,则这样的点Q ( ) A.有且仅有1个 B.有且仅有2个 C.有且仅有3个 D.可以有无数个11.(填空题,4分)已知向量 a ⃗ =(1,-2), b ⃗⃗ =(3,1),则 a ⃗ +2 b ⃗⃗ =___ . 12.(填空题,4分)已知cosα4sinα−2cosα=16,则tanα=___ .13.(填空题,4分)在△ABC 中,点D 满足 BD ⃗⃗⃗⃗⃗⃗⃗=4DC ⃗⃗⃗⃗⃗⃗ ,若 AD ⃗⃗⃗⃗⃗⃗=xAB ⃗⃗⃗⃗⃗⃗+yAC ⃗⃗⃗⃗⃗⃗ ,则x-y=___ . 14.(填空题,4分)已知函数 f (x )=sin (ωx +φ)(ω>0,|φ|<π2) 在区间 (π3,4π3) 上单调,且对任意实数x 均有 f (4π3)≤f (x )≤f (π3) 成立,则φ=___ .15.(填空题,4分)声音是由物体振动而产生的声波通过介质(空气、固体或液体)传播并能被人的听觉器官所感知的波动现象.在现实生活中经常需要把两个不同的声波进行合成,这种技术被广泛运用在乐器的调音和耳机的主动降噪技术方面.(1)若甲声波的数学模型为f 1(t )=sin200πt ,乙声波的数学模型为f 2(t )=sin (200πt+φ)(φ>0),甲、乙声波合成后的数学模型为f (t )=f 1(t )+f 2(t ).要使f (t )=0恒成立,则φ的最小值为;(2)技术人员获取某种声波,其数学模型记为H (t ),其部分图象如图所示,对该声波进行逆向分析,发现它是由S 1,S 2两种不同的声波合成得到的,S 1,S 2的数学模型分别记为f (t )和g (t ),满足H (t )=f (t )+g (t ).已知S 1,S 2两种声波的数学模型源自于下列四个函数中的两个.① y =sin π2t ; ② y=sin2πt ; ③ y=sin3πt ; ④ y=2sin3πt . 则S 1,S 2两种声波的数学模型分别是___ .(填写序号)16.(问答题,9分)已知函数 f (x )=1−cos 2xsinx. (Ⅰ)求f (x )的定义域; (Ⅱ)若 f (θ)=2√55,且 θ∈(π2,π) ,求tan (π-θ)的值.17.(问答题,9分)已知点A (5,-2),B (-1,4),C (3,3),M 是线段AB 的中点. (Ⅰ)求点M 和 AB ⃗⃗⃗⃗⃗⃗ 的坐标;(Ⅱ)若D 是x 轴上一点,且满足 BD ⃗⃗⃗⃗⃗⃗⃗∥CM ⃗⃗⃗⃗⃗⃗⃗ ,求点D 的坐标.18.(问答题,11分)已知函数 f (x )=2sin (x −π3) . (Ⅰ)某同学利用五点法画函数f (x )在区间 [π3,7π3] 上的图象.他列出表格,并填入了部分数据,请你帮他把表格填写完整,并在坐标系中画出图象;xπ3 5π6 11π6 7π3 x −π3π 3π2 2π f (x )2(ⅰ)若函数g (x )的最小正周期为 2π3 ,求g (x )的单调递增区间;(ⅱ)若函数g (x )在 [0,π3] 上无零点,求ω的取值范围(直接写出结论).19.(问答题,11分)若定义域R 的函数f (x )满足:① ∀x 1,x 2∈R ,(x 1-x 2)[f (x 1)-f (x 2)]≥0, ② ∃T >0,∀x∈R ,f (x+T )=f (x )+1.则称函数f (x )满足性质P (T ).(Ⅰ)判断函数f (x )=2x 与g (x )=sinx 是否满足性质P (T ),若满足,求出T 的值; (Ⅱ)若函数f (x )满足性质P (2),判断是否存在实数a ,使得对任意x∈R ,都有f (x+a )-f (x )=2021,并说明理由;(Ⅲ)若函数f (x )满足性质P (4),且f (-2)=0.对任意的x∈(-2,2),都有f (-x )=-f (x ),求函数 g (t )=tf (t )+f (t )f(4t)的值域.2020-2021学年北京市海淀区高一(下)期中数学试卷参考答案与试题解析试题数:19,总分:1001.(单选题,4分)若角α的终边经过点P (-2,3),则tanα=( ) A. −23 B. 23 C. −32 D. 32【正确答案】:C【解析】:利用任意角的三角函数的定义求解.【解答】:解:∵角α的终边经过点P (-2,3), ∴tanα= 3−2 =- 32 , 故选:C .【点评】:本题主要考查了任意角的三角函数的定义,是基础题. 2.(单选题,4分)已知向量 a ⃗ =(1,2),则| a ⃗ |=( ) A.3 B. √3 C.5 D. √5【正确答案】:D【解析】:根据题意,由向量的坐标结合向量的模的计算公式,计算可得答案.【解答】:解:根据题意,向量 a ⃗ =(1,2),则| a ⃗ |= √12+22 = √5 , 即| a ⃗ |= √5 , 故选:D .【点评】:本题考查向量模的计算,关键是理解向量的坐标以及向量模的定义.3.(单选题,4分) MB ⃗⃗⃗⃗⃗⃗⃗−BA ⃗⃗⃗⃗⃗⃗+BO ⃗⃗⃗⃗⃗⃗+OM ⃗⃗⃗⃗⃗⃗⃗ =( ) A. AB ⃗⃗⃗⃗⃗⃗ B. BA ⃗⃗⃗⃗⃗⃗ C. MB ⃗⃗⃗⃗⃗⃗⃗ D. BM ⃗⃗⃗⃗⃗⃗⃗【正确答案】:A【解析】:根据向量的减法的运算法则进行求解即可.【解答】:解:因为: MB ⃗⃗⃗⃗⃗⃗⃗−BA ⃗⃗⃗⃗⃗⃗+BO ⃗⃗⃗⃗⃗⃗+OM ⃗⃗⃗⃗⃗⃗⃗ = OM ⃗⃗⃗⃗⃗⃗⃗ + MB ⃗⃗⃗⃗⃗⃗⃗ + BO ⃗⃗⃗⃗⃗⃗ - BA ⃗⃗⃗⃗⃗⃗ = AB ⃗⃗⃗⃗⃗⃗ , 故选:A .【点评】:本题主要考查平面向量的基本运算,比较基础.4.(单选题,4分)在△ABC 中,A 为钝角,则点P (cosA ,tanB )( ) A.在第一象限 B.在第二象限 C.在第三象限 D.在第四象限 【正确答案】:B【解析】:根据三角形内角和定理与三角函数值的符号法则,判断即可.【解答】:解:△ABC 中,A 为钝角,所以B 为锐角, 所以cosA <0,tanB >0,所以点P (cosA ,tanB )在第二象限内. 故选:B .【点评】:本题考查了三角形内角和定理与三角函数值符号的判断问题,是基础题. 5.(单选题,4分)下列函数中,周期为π且在区间( π2 ,π)上单调递增的是( ) A.y=cos2x B.y=sin2x C. y =cos 12x D. y =sin 12x 【正确答案】:A【解析】:利用三角函数的周期性和单调性即可求解.【解答】:解:对于A,y=cos2x的周期为π,在区间(π2,π)单调递增函数,所以正确;对于B,y=sin2x的周期为π,在区间(π2,π)不是单调函数,所以不正确;对于C,y=cos 12 x的周期为2π12=4π,所以不正确;对于D,y=sin 12 x的周期为2π12=4π,所以不正确;故选:A.【点评】:本题考查三角函数的周期性以及单调性的判断,是基础题.6.(单选题,4分)对函数y=sinx的图象分别作以下变换:① 向左平移π4个单位,再将每个点的横坐标缩短为原来的13(纵坐标不变);② 向左平移π12个单位,再将每个点的横坐标缩短为原来的13(纵坐标不变)③ 将每个点的横坐标缩短为原来的13(纵坐标不变),再向左平移π4个单位④ 将每个点的横坐标缩短为原来的13(纵坐标不变),再向左平移π12个单位其中能得到函数y=sin(3x+π4)的图象的是()A. ① ③B. ② ③C. ① ④D. ② ④【正确答案】:C【解析】:根据三角函数沿x轴的平移变换和伸缩变换,看哪个变换可由y=sinx得到y=sin(3x+π4)即可.【解答】:解:① y=sinx→ y=sin(x+π4)→ y=sin(3x+π4);② y=sinx→ y=sin(x+π12)→ y=sin(3x+π12);③ y=sinx→y=sin3x→ y=sin3(x+π4);④ y=sinx→y=sin3x→ y=sin3(x+π12)=sin(3x+π4).故选:C.【点评】:本题考查了三角函数沿x轴方向的平移变换和伸缩变换,考查了计算能力,属于基础题.7.(单选题,4分)如图,已知向量a⃗,b⃗⃗,c⃗,d⃗,e⃗的起点相同,则c⃗ + d⃗ - e⃗ =()A.- b⃗⃗B. b⃗⃗C.-6 a⃗ + b⃗⃗D.6 a⃗ - b⃗⃗【正确答案】:D【解析】:利用平面向量的基本定理,推出结果即可.【解答】:解:如图,已知向量a⃗,b⃗⃗,c⃗,d⃗,e⃗的起点相同,则c⃗ + d⃗ - e⃗ = a⃗+b⃗⃗ +(2 a⃗−2b⃗⃗)-(-3 a⃗)=6 a⃗ - b⃗⃗.故选:D.【点评】:本题考查向量的基本定理的应用,向量的加减运算,是基础题.8.(单选题,4分)已知函数f(x)=2sin(ωx+φ)(ω>0,|φ|<π2)的图象如图所示,则ω的值为()A.2B.1C. 12D. 14【正确答案】:C【解析】:由点(0,√2)在函数的图象上可求sinφ= √22,结合范围|φ|<π2,可得φ= π4,又点(2π,- √2)在函数的图象上,有sin(2πω+ π4)=- √22,可得2πω+ π4=2kπ- π4,或2kπ- 3π4,k∈Z,从而解得ω的值.【解答】:解:∵点(0,√2)在函数的图象上,即有2sinφ= √2,∴sinφ= √22,∵|φ|<π2,∴可得:φ= π4,又∵点(2π,- √2)在函数的图象上,即有2sin(2πω+ π4)=- √2,∴sin(2πω+ π4)=- √22,可得2πω+ π4=2kπ- π4,或2kπ- 3π4,k∈Z,∴解得ω=k- 14,或ω=k- 12,k∈Z,则当k=1时,ω的值为12.故选:C.【点评】:本题考查由y=Asin(ωx+φ)的部分图象确定其解析式,理解三角函数图象的特征是解题的关键,属于基础题.9.(单选题,4分)“sinα=cosβ”是“ α+β=π2+2kπ(k∈Z)”的()A.充分而不必要条件B.必要而不充分条件C.充分必要条件D.既不充分也不必要条件【正确答案】:B【解析】:sinα=cosβ⇒cos(π2 -α)=cosβ,可得β=2kπ±(π2-α),k∈Z.即可判断出结论.【解答】:解:sinα=cosβ⇒cos(π2-α)=cosβ,∴β=2kπ±(π2-α),k∈Z.化为:α+β= π2+2kπ,k∈Z,或β-α=- π2+2kπ,k∈Z,∴“sinα=cosβ“是“α+β= π2+2kπ,k∈Z“的必要不充分条件.故选:B.【点评】:本题考查了三角函数方程的解法、简易逻辑的判定方法,考查了推理能力与计算能力,属于基础题.10.(单选题,4分)已知函数f (x )=(x-1)3.Q 是f (x )的图象上一点,若在f (x )的图象上存在不同的两点M ,N ,使得 OM ⃗⃗⃗⃗⃗⃗⃗=2OQ ⃗⃗⃗⃗⃗⃗⃗−ON ⃗⃗⃗⃗⃗⃗⃗ 成立,其中O 是坐标原点,则这样的点Q ( ) A.有且仅有1个 B.有且仅有2个 C.有且仅有3个 D.可以有无数个 【正确答案】:A【解析】:先由已知可得Q 为M ,N 的中点,然后根据函数f (x )的对称性即可做出判断.【解答】:解:因为 OM ⃗⃗⃗⃗⃗⃗⃗=2OQ ⃗⃗⃗⃗⃗⃗⃗−ON ⃗⃗⃗⃗⃗⃗⃗ ,则 OM ⃗⃗⃗⃗⃗⃗⃗+ON ⃗⃗⃗⃗⃗⃗⃗=2OQ ⃗⃗⃗⃗⃗⃗⃗ ,所以Q 为MN 的中点, 因为函数f (x )=(x-1)3关于点(1,0)成中心对称,所以当Q 的坐标为(1,0)时,取关于点Q 对称的点M ,N 符合题意, M ,N 在(1,0)两侧时,中点也要在函数f (x )上,只能是(1,0),M ,N 在(1,0)同侧时,相当于M ,Q ,N 所在的直线与f (x )在一侧有3个交点,不可能成立,故满足条件的Q 只有一个, 故选:A .【点评】:本题考查了平面向量基本定理的应用,涉及到函数的对称性,考查了学生的分析问题的能力,属于中档题.11.(填空题,4分)已知向量 a ⃗ =(1,-2), b ⃗⃗ =(3,1),则 a ⃗ +2 b ⃗⃗ =___ . 【正确答案】:[1](7,0)【解析】:根据向量的坐标运算求出 a ⃗ +2 b ⃗⃗ 的坐标即可.【解答】:解:∵ a ⃗ =(1,-2), b ⃗⃗ =(3,1), ∴ a ⃗ +2 b⃗⃗ =(1,-2)+2(3,1)=(7,0), 故答案为:(7,0).【点评】:本题考查了向量的坐标运算,考查对应思想,是基础题. 12.(填空题,4分)已知 cosα4sinα−2cosα=16 ,则tanα=___ . 【正确答案】:[1]2【解析】:对已知等式分子分母同时除以cosα,即可求出tanα的值.【解答】:解:∵ cosα4sinα−2cosα=16 , ∴ 14tanα−2=16 , ∴4tanα-2=6, ∴tanα=2, 故答案为:2.【点评】:本题主要考查了同角三角函数间的基本关系,是基础题.13.(填空题,4分)在△ABC 中,点D 满足 BD ⃗⃗⃗⃗⃗⃗⃗=4DC ⃗⃗⃗⃗⃗⃗ ,若 AD ⃗⃗⃗⃗⃗⃗=xAB ⃗⃗⃗⃗⃗⃗+yAC ⃗⃗⃗⃗⃗⃗ ,则x-y=___ . 【正确答案】:[1]- 35【解析】:利用已知条件画出图形,利用平面向量的基本定理,求解x ,y 即可.【解答】:解:在△ABC 中,点D 满足 BD ⃗⃗⃗⃗⃗⃗⃗=4DC ⃗⃗⃗⃗⃗⃗ ,若 AD ⃗⃗⃗⃗⃗⃗=xAB ⃗⃗⃗⃗⃗⃗+yAC ⃗⃗⃗⃗⃗⃗ , 如图,可知 AD ⃗⃗⃗⃗⃗⃗ = 15 AB ⃗⃗⃗⃗⃗⃗ +45 AC ⃗⃗⃗⃗⃗⃗ , 所以x= 15 ,y= 45 , 则x-y=- 35 . 故答案为:- 35 .【点评】:本题考查平面向量的基本定理的应用,是基础题. 14.(填空题,4分)已知函数 f (x )=sin (ωx +φ)(ω>0,|φ|<π2) 在区间 (π3,4π3) 上单调,且对任意实数x 均有f (4π3)≤f (x )≤f (π3) 成立,则φ=___ . 【正确答案】:[1] π6【解析】:由题意利用正弦函数的图象和性质,先求出ω,再根据五点法作图,可得φ的值.【解答】:解:∵函数 f (x )=sin (ωx +φ)(ω>0,|φ|<π2) 在区间 (π3,4π3) 上单调,且对任意实数x 均有 f (4π3)≤f (x )≤f (π3) 成立,∴ 1 2• 2πω= 4π3- π3,∴ω=1.且π3是f(x)的最大值点,4π3是函数f(x)的最小值点,由五点法作图可得1× π3+φ= π2,∴φ= π6,故答案为:π6.【点评】:本题主要考查正弦函数的图象和性质,属于中档题.15.(填空题,4分)声音是由物体振动而产生的声波通过介质(空气、固体或液体)传播并能被人的听觉器官所感知的波动现象.在现实生活中经常需要把两个不同的声波进行合成,这种技术被广泛运用在乐器的调音和耳机的主动降噪技术方面.(1)若甲声波的数学模型为f1(t)=sin200πt,乙声波的数学模型为f2(t)=sin(200πt+φ)(φ>0),甲、乙声波合成后的数学模型为f(t)=f1(t)+f2(t).要使f(t)=0恒成立,则φ的最小值为;(2)技术人员获取某种声波,其数学模型记为H(t),其部分图象如图所示,对该声波进行逆向分析,发现它是由S1,S2两种不同的声波合成得到的,S1,S2的数学模型分别记为f(t)和g(t),满足H(t)=f(t)+g(t).已知S1,S2两种声波的数学模型源自于下列四个函数中的两个.① y=sinπ2t;② y=sin2πt;③ y=sin3πt;④ y=2sin3πt.则S1,S2两种声波的数学模型分别是___ .(填写序号)【正确答案】:[1] ② ③【解析】:(1)由函数f(t)的解析式以及正弦型函数的性质,即可解出;(2)由函数图象分析可知至少有一个数学模型的振幅大于等于2,由此可知④ 是必选,再利用函数图象及其周期性可作出判断.【解答】:解:(1)由题意可知sin200πt=-sin(200πt+φ),又∵sin(π+α)=-sinα,∴φmin=π,(2)当t=1时,y=sinπ2=1,y=sin2π=0,y=sin3π=0,y=2sin3π=0,由图象可知H(1)=0,∴排出① ,由图象可知,波峰波谷是不一样波动的,且有三种不同的波峰,则说明f(t),g(t)的周期不同,而③ ④ 的周期相同,∴一定包含② y=sin2πt,若② ④ 组合,当t= 16时,H(16)=sin(2π× 16)+2sin(3π× 16)= √32+2>3,与图象不符,∴排除④ ,∴只能是② ③ .故答案为:π,② ③ .【点评】:本题考查了函数模型的实际应用,学生的数学运算能力,分析问题能力,属于基础题.16.(问答题,9分)已知函数f(x)=1−cos2xsinx.(Ⅰ)求f(x)的定义域;(Ⅱ)若f(θ)=2√55,且θ∈(π2,π),求tan(π-θ)的值.【正确答案】:【解析】:(Ⅰ)由sinx≠0即可求出f(x)的定义域.(Ⅱ)先化简函数f(x)的解析式,再代入f(θ)=2√55,得到sinθ= 2√55,在根据同角三角函数间的基本关系和角θ的范围求解即可.【解答】:解:(Ⅰ)由题意可知sinx≠0,∴x≠kπ(k∈Z),∴f(x)的定义域为{x|x≠kπ,k∈Z}.(Ⅱ)f(x)=1−cos 2xsinx = sin2xsinx=sinx,∵ f(θ)=2√55,∴sinθ= 2√55,又∵ θ∈(π2,π),∴cosθ=- √1−sin2θ =- √55,∴tan(π-θ)=-tanθ=- sinθcosθ=2.【点评】:本题主要考查了三角函数的恒等变形及化简,考查了同角三角函数间的基本关系,是基础题.17.(问答题,9分)已知点A (5,-2),B (-1,4),C (3,3),M 是线段AB 的中点. (Ⅰ)求点M 和 AB ⃗⃗⃗⃗⃗⃗ 的坐标;(Ⅱ)若D 是x 轴上一点,且满足 BD ⃗⃗⃗⃗⃗⃗⃗∥CM ⃗⃗⃗⃗⃗⃗⃗ ,求点D 的坐标.【正确答案】:【解析】:(Ⅰ)根据向量的运算性质计算即可;(Ⅱ)根据向量的线性运算计算即可.【解答】:解:(Ⅰ)∵A (5,-2),B (-1,4),M 是线段AB 的中点, ∴M (5−12 , −2+42)=(2,1), AB ⃗⃗⃗⃗⃗⃗ = OB ⃗⃗⃗⃗⃗⃗ - OA ⃗⃗⃗⃗⃗⃗ =(-1,4)-(5,-2)=(-6,6);(Ⅱ)设D (x ,0),则 BD ⃗⃗⃗⃗⃗⃗⃗ =(x+1,-4), CM ⃗⃗⃗⃗⃗⃗⃗ =(-1,-2), ∵ BD ⃗⃗⃗⃗⃗⃗⃗∥CM ⃗⃗⃗⃗⃗⃗⃗ ,∴(x+1)•(-2)-(-4)•(-1)=0,解得:x=-3, ∴点D 的坐标是(-3,0).【点评】:本题考查了向量的坐标运算,考查平行向量,是基础题. 18.(问答题,11分)已知函数 f (x )=2sin (x −π3) . (Ⅰ)某同学利用五点法画函数f (x )在区间 [π3,7π3] 上的图象.他列出表格,并填入了部分数据,请你帮他把表格填写完整,并在坐标系中画出图象;xπ35π611π6 7π3x−π3π3π22πf(x) 2(Ⅱ)已知函数g(x)=f(ωx)(ω>0).(ⅰ)若函数g(x)的最小正周期为2π3,求g(x)的单调递增区间;(ⅱ)若函数g(x)在[0,π3]上无零点,求ω的取值范围(直接写出结论).【正确答案】:【解析】:(Ⅰ)利用正弦函数的性质及五点作图法即可求解;(Ⅱ)(ⅰ)由已知可求g(x)=2sin(ωx- π3),利用正弦函数的周期公式可求ω=3,利用正弦函数的单调性即可求解;(ⅱ)利用正弦函数的性质即可求解.【解答】:解:(Ⅰ)表格如下:x π35π611π67π3x−π3π2π3π22πf(x) 2 -2 图像如下:(Ⅱ)已知函数g(x)=f(ωx)(ω>0).(ⅰ)∵ f (x )=2sin (x −π3) ,g (x )=f (ωx )(ω>0). ∴g (x )=2sin (ωx - π3 ),∵函数g (x )的最小正周期为 2π3 = 2πω ,解得ω=3, ∴g (x )=2sin (3x- π3),令2kπ- π2 ≤3x - π3 ≤2kπ+ π2 ,k∈Z ,解得- π18 + 2kπ3 ≤x≤ 5π18 + 2kπ3,k∈Z , 可得g (x )的单调递增区间为[- π18 + 2kπ3 , 5π18 + 2kπ3],k∈Z ; (ⅱ)ω的取值范围为(0,1).【点评】:本题主要考查了五点法作函数y=Asin (ωx+φ)的图象,正弦函数的单调性,考查了数形结合思想和函数思想的应用,属于中档题. 19.(问答题,11分)若定义域R 的函数f (x )满足:① ∀x 1,x 2∈R ,(x 1-x 2)[f (x 1)-f (x 2)]≥0, ② ∃T >0,∀x∈R ,f (x+T )=f (x )+1.则称函数f (x )满足性质P (T ).(Ⅰ)判断函数f (x )=2x 与g (x )=sinx 是否满足性质P (T ),若满足,求出T 的值; (Ⅱ)若函数f (x )满足性质P (2),判断是否存在实数a ,使得对任意x∈R ,都有f (x+a )-f (x )=2021,并说明理由;(Ⅲ)若函数f (x )满足性质P (4),且f (-2)=0.对任意的x∈(-2,2),都有f (-x )=-f (x ),求函数 g (t )=tf (t )+f (t )f(4t)的值域.【正确答案】:【解析】:(Ⅰ)利用定义分别判断即可求解得结论;(Ⅱ)由 ② 计算可得f (x+2n )=f (x )+n ,即f (x+2n )-f (x )=n ,令n=2021即可求得a 的值;(Ⅲ)根据已知可得任意的x∈[-2,2),f (x )=0,递推可得任意的x∈[4k -2,4k+2),k∈Z ,有f (x )=k ,由f (t )≠0,可得t∉[-2,2),分t=2,|t|>2两种情况分别求出g (t )的值域即可得解.【解答】:解:(Ⅰ)函数f (x )=2x 为增函数,满足性质 ① , 对于 ② ,由∀x∈R ,f (x+T )=f (x )+1有2(x+T )=2x+1, 所以2T=1,T= 12,所以函数f (x )=2x 满足性质P ( 12 ).函数g (x )=sinx 显然不满足 ① ,所以不满足性质P (T ). (Ⅱ)存在,理由如下: 由∀x∈R ,f (x+2)=f (x )+1.可得f (x+2n )=f (x+2n-2)+1=f (x+2n-4)+2=f (x+2n-6)+3=…=f (x )+n (n∈N*), 即f (x+2n )-f (x )=n , 令n=2021,得a=2n=4042.(Ⅲ)依题意,对任意的x∈(-2,2),都有f (-x )=-f (x ),所以f (0)=0, 因为函数f (x )满足性质P (4),由 ① 可得,在区间[-2,0]上有f (-2)≤f (x )≤f (0),又因为f (-2)=0,所以0≤f (x )≤0,可得任意x ∈[-2,0],f (x )=0, 又因为对任意的x∈(-2,2),都有f (-x )=-f (x ), 所以任意的x∈[-2,2),f (x )=0,递推可得任意的x∈[4k -2,4k+2),k∈Z ,有f (x )=k , 函数g (t )=tf (t )(f(4t)+1),因为f (t )≠0,所以t∉[-2,2),由 ② 及f (-2)=0,可得f (2)=1, 所以当t=2时,g (2)= 21×(1+1) =1, 当|t|>2时, 4t ∈(-2,2),所以f ( 4t )=0, 即|t|>2时,g (t )= tf (t ) ,所以当t∈[4k -2,4k+2)(k∈Z ,k≠0,t≠2)时,g (t )= tk , 当k≥1时,g (t )∈[4k−2k , 4k+2k )=[4- 2k ,4+ 2k)(当k=1时,g (t )≠2,需要排除),此时 2k 随k 的增大而减小,所以[4- 2k+1 ,4+ 2k+1 )⫋[4- 2k ,4+ 2k ), 所以求值域,只需取k=1,得g (t )∈[4- 21 ,4+ 21 )=[2,6), 当k <0时,g (t )∈(4k+2k , 4k−2k ]=(4+ 2k ,4- 2k], 此时 2k 随k 的增大而减小,所以(4+ 2k−1 ,4- 2k−1 ]⫋(4+ 2k ,4- 2k ], 只需取k=-1,得g (t )∈(4+ 2−1 ,4- 2−1 ]=(2,6].综上,函数g(t)的值域为{1}∪(2,6].【点评】:本题主要考查抽象函数及其应用,考查新定义,函数值域的求法,考查逻辑推理与运算求解能力,属于难题.。

2020-2021学年北京市丰台区高一(下)期中数学试卷(A卷)

2020-2021学年北京市丰台区高一(下)期中数学试卷(A卷)

2020-2021学年北京市丰台区高一(下)期中数学试卷(A 卷)试题数:20,总分:1001.(单选题,4分)设i 是虚数单位,则复数z=1+3i 的共轭复数是( )A.1+3iB.1-3iC.-1+3iD.-1-3i2.(单选题,4分)函数f (x )=cos2x 的图象中,相邻两条对称轴之间的距离是( )A.2πB.πC. π2D. π4 3.(单选题,4分)已知向量 a ⃗ =(4,x ), b ⃗⃗ =(x ,1),那么“x=2”是“ a ⃗ || b⃗⃗ ”的( ) A.充分而不必要条件B.必要而不充分条件C.充分必要条件D.既不充分也不必要条件4.(单选题,4分)函数 f (x )=sin (2x +π4) 的图象,向右平移 π4 个单位长度后得到函数g (x )的解析式为( )A.g (x )=sin2xB. g (x )=sin (2x +π4)C. g (x )=sin (2x −π4)D. g (x )=sin (2x +3π4) 5.(单选题,4分)如图,在平行四边形ABCD 中,E 是BC 的中点, AE ⃗⃗⃗⃗⃗⃗=3AF ⃗⃗⃗⃗⃗⃗ ,则 DF ⃗⃗⃗⃗⃗⃗ =( )A. −13AB ⃗⃗⃗⃗⃗⃗+23AD ⃗⃗⃗⃗⃗⃗B. 13AB ⃗⃗⃗⃗⃗⃗−23AD ⃗⃗⃗⃗⃗⃗C. 13AB ⃗⃗⃗⃗⃗⃗−34AD ⃗⃗⃗⃗⃗⃗D. 13AB ⃗⃗⃗⃗⃗⃗−56AD ⃗⃗⃗⃗⃗⃗ 6.(单选题,4分)下列各数a=sin25°cos27°+cos25°sin27°,b=2sin27°cos27°,c=2cos 222°-1, d =2tan22.5°1−tan 222.5° 中,最大的是( )A.aB.bC.cD.d7.(单选题,4分)已知向量 BA ⃗⃗⃗⃗⃗⃗ =( 12 , √32 ), BC ⃗⃗⃗⃗⃗⃗ =( √32 , 12 ),则∠ABC=( ) A.30°B.60°C.90°D.120°8.(单选题,4分)函数f (x )=2sin (ωx+φ)(ω>0,|φ|< π2 )的部分图象如图所示,则f (π)=( )A.- √3B.- √32C. √32D. √39.(单选题,4分)已知△ABC 是边长为1的等边三角形,设D ,E 分别是边AB ,BC 的中点,连接DE 并延长到点F ,使得DE=EF ,则 AF⃗⃗⃗⃗⃗⃗•BC⃗⃗⃗⃗⃗⃗ =( ) A.0B. 14C. 18D. 5810.(单选题,4分)已知平面上的两个单位向量 a ⃗ , b ⃗⃗ 满足 a ⃗ ⋅ b ⃗⃗ = 45 ,若m∈R ,则| a ⃗ +m b ⃗⃗ |的最小值为( )A. 52B. 25C. 53D. 3511.(填空题,4分)已知i 为虚数单位,若(1+i )z=2i ,则|z|=___ .12.(填空题,4分)已知非零向量 a ⃗ , b ⃗⃗ 满足| b ⃗⃗ |=2| a ⃗ |,且( a ⃗ + b ⃗⃗ )⊥ a ⃗ ,则 a ⃗ 与 b⃗⃗ 的夹角为___ .13.(填空题,4分)在△ABC 中,a= √2 b ,b= √3c ,则最大角的余弦值为___ .14.(填空题,4分)已知向量 a ⃗ , b ⃗⃗ 是单位向量, a ⃗ 与 b ⃗⃗ 的夹角为120°,则( a ⃗ + b⃗⃗ )⋅ b ⃗⃗ =___ ,| a ⃗ +2 b⃗⃗ |=___ . 15.(填空题,4分)一艘货船以20km/h 的速度向东航行,货船在A 处看到一个灯塔P 在北偏东60°方向上,行驶4小时后,货船到达B 处,此时看到灯塔P 在北偏东15°方向上,这时船与灯塔的距离为___ km .16.(填空题,4分)梯形ABCD 中,AB || CD ,AB=2,AD=CD=1,∠BAD=90°,点P 在线段BC 上运动.(1)当点P 是线段BC 的中点时, BC ⃗⃗⃗⃗⃗⃗•AP⃗⃗⃗⃗⃗⃗ =___ ; (2) PB ⃗⃗⃗⃗⃗⃗•AP⃗⃗⃗⃗⃗⃗ 的最大值是___ . 17.(问答题,9分)已知A (-1,2),B (3,3),C (t ,1).(Ⅰ)当A ,B ,C 三点共线时,求实数t 的值;(Ⅱ)若∠ABC=90°,求实数t 的值;(Ⅲ)当t=6时,点A ,B ,C ,D 构成平行四边形ABCD ,求点D 的坐标.18.(问答题,9分)已知函数f (x )=sin 2x .(Ⅰ)求 f (π3) 的值;(Ⅱ)若 f (α)=23 ,求cos2α的值;(Ⅲ)设函数 g (x )=f (x )+√3sinxcosx ,求函数g (x )的单调递增区间.19.(问答题,9分)在△ABC中,sinA+√3cosA=0,a=√19,b=2.(Ⅰ)求A的大小及边c的值;(Ⅱ)若D是BC边上的一点,且AD⊥AC,求△ABD的面积.20.(问答题,9分)在△ABC中,角A,B,C的对边分别为a,b,c,且a2+b2=√3ab+ c2.(Ⅰ)求C的值;(Ⅱ)求cosA+sinB的最大值.2020-2021学年北京市丰台区高一(下)期中数学试卷(A卷)参考答案与试题解析试题数:20,总分:1001.(单选题,4分)设i是虚数单位,则复数z=1+3i的共轭复数是()A.1+3iB.1-3iC.-1+3iD.-1-3i【正确答案】:B【解析】:由已知直接利用共轭复数的概念得答案.【解答】:解:∵z=1+3i,∴ z=1−3i,故选:B.【点评】:本题考查复数的基本概念,是基础题.2.(单选题,4分)函数f(x)=cos2x的图象中,相邻两条对称轴之间的距离是()A.2πB.πC. π2D. π4【正确答案】:C【解析】:由题意利用余弦函数的周期性,可得相邻两条对称轴之间的距离为T2,计算求得结果.【解答】:解:函数f(x)=cos2x的图象中,相邻两条对称轴之间的距离为T2 = πω= π2,故选:C.【点评】:本题主要考查余弦函数的周期性,属于基础题.3.(单选题,4分)已知向量 a ⃗ =(4,x ), b ⃗⃗ =(x ,1),那么“x=2”是“ a ⃗ || b⃗⃗ ”的( ) A.充分而不必要条件B.必要而不充分条件C.充分必要条件D.既不充分也不必要条件【正确答案】:A【解析】:先化简命题,再讨论充要性.【解答】:解:向量 a ⃗ =(4,x ), b ⃗⃗ =(x ,1), a ⃗ || b⃗⃗ ,则4=x 2,解之得x=±2, 则“x=2”是“x=±2”的充分而不必要条件,即向量 a ⃗ =(4,x ), b ⃗⃗ =(x ,1),那么“x=2”是“ a ⃗ || b⃗⃗ ”的充分而不必要条件, 故选:A .【点评】:本题考查命题充要性,以及向量平行,属于基础题.4.(单选题,4分)函数 f (x )=sin (2x +π4) 的图象,向右平移 π4 个单位长度后得到函数g (x )的解析式为( )A.g (x )=sin2xB. g (x )=sin (2x +π4)C. g (x )=sin (2x −π4)D. g (x )=sin (2x +3π4) 【正确答案】:C【解析】:直接利用三角函数的关系式的平移变换的应用求出结果.【解答】:解:函数 f (x )=sin (2x +π4) 的图象,向右平移 π4 个单位长度后得到函数g (x )=sin (2x- π2+π4 )=sin (2x- π4 )的图象.故选:C .【点评】:本题考查的知识要点:三角函数的关系式的平移变换的应用,主要考查学生的运算能力和数学思维能力,属于基础题.5.(单选题,4分)如图,在平行四边形ABCD 中,E 是BC 的中点, AE ⃗⃗⃗⃗⃗⃗=3AF⃗⃗⃗⃗⃗⃗ ,则 DF ⃗⃗⃗⃗⃗⃗ =( )A. −13AB⃗⃗⃗⃗⃗⃗+23AD ⃗⃗⃗⃗⃗⃗ B. 13AB ⃗⃗⃗⃗⃗⃗−23AD ⃗⃗⃗⃗⃗⃗C. 13AB ⃗⃗⃗⃗⃗⃗−34AD ⃗⃗⃗⃗⃗⃗D. 13AB ⃗⃗⃗⃗⃗⃗−56AD ⃗⃗⃗⃗⃗⃗【正确答案】:D【解析】:利用三角形法则即可求解.【解答】:解:在平行四边形中,由已知可得:DF ⃗⃗⃗⃗⃗⃗=AF ⃗⃗⃗⃗⃗⃗−AD ⃗⃗⃗⃗⃗⃗ = 13AE ⃗⃗⃗⃗⃗⃗ - AD ⃗⃗⃗⃗⃗⃗ = 13(AB ⃗⃗⃗⃗⃗⃗+12BC ⃗⃗⃗⃗⃗⃗)−AD ⃗⃗⃗⃗⃗⃗ = 13AB ⃗⃗⃗⃗⃗⃗+16AD ⃗⃗⃗⃗⃗⃗−AD ⃗⃗⃗⃗⃗⃗ = 13AB ⃗⃗⃗⃗⃗⃗−56AD ⃗⃗⃗⃗⃗⃗ , 故选:D .【点评】:本题考查了平面向量基本定理的应用,考查了学生的运算能力,属于基础题.6.(单选题,4分)下列各数a=sin25°cos27°+cos25°sin27°,b=2sin27°cos27°,c=2cos 222°-1, d =2tan22.5°1−tan 222.5° 中,最大的是( )A.aB.bC.cD.d【正确答案】:D【解析】:先结合二倍角公式进行化简,然后结合正弦函数的单调性即可比较大小.【解答】:解:a=sin25°cos27°+cos25°sin27°=sin42°,b=2sin27°cos27°=sin54°,c=2cos 222°-1=cos44°=sin46°, d =2tan22.5°1−tan 222.5° =tan45°=1, 因为y=sinx 在(0, π2 )上单调递增,所以sin42°<sin46°<sin54°<1=tan45°,所以a <c <b <d .即最大的为d .故选:D .【点评】:本题主要考查了二倍角公式及正弦函数的单调性的应用,属于基础题.7.(单选题,4分)已知向量 BA ⃗⃗⃗⃗⃗⃗ =( 12 , √32 ), BC ⃗⃗⃗⃗⃗⃗ =( √32 , 12 ),则∠ABC=( ) A.30°B.60°C.90°D.120°【正确答案】:A【解析】:根据题意,由 BA ⃗⃗⃗⃗⃗⃗ 、 BC ⃗⃗⃗⃗⃗⃗ 的坐标可得则| BA ⃗⃗⃗⃗⃗⃗ |、| BC ⃗⃗⃗⃗⃗⃗ |、 BA ⃗⃗⃗⃗⃗⃗ • BC⃗⃗⃗⃗⃗⃗ 的值,由向量夹角公式可得cos∠ABC 的值,进而分析可得答案.【解答】:解:根据题意,向量 BA ⃗⃗⃗⃗⃗⃗ =( 12 , √32 ), BC ⃗⃗⃗⃗⃗⃗ =( √32 , 12 ), 则| BA ⃗⃗⃗⃗⃗⃗ |=1,| BC ⃗⃗⃗⃗⃗⃗ |=1,则 BA ⃗⃗⃗⃗⃗⃗ • BC ⃗⃗⃗⃗⃗⃗ = 12 × √32 + 12 × √32 = √32, 则cos∠ABC= BA ⃗⃗⃗⃗⃗⃗•BC ⃗⃗⃗⃗⃗⃗|BA ⃗⃗⃗⃗⃗⃗||BC⃗⃗⃗⃗⃗⃗| = √32 , 又由0°≤∠ABC≤180°,则∠ABC=30°,故选:A .【点评】:本题考查向量数量积的计算,涉及向量的坐标计算,属于基础题.8.(单选题,4分)函数f (x )=2sin (ωx+φ)(ω>0,|φ|< π2)的部分图象如图所示,则f (π)=( )A.- √3B.- √32C. √32D. √3【正确答案】:A【解析】:由已知函数图象求得T ,进一步得到ω,再由五点作图的第二点求得φ,则函数解析式可求,从而可得f (π).【解答】:解:由图可知, T 2 = 5π12 -(- π12 )= π2 ,则T=π,∴ω=2.又2× 5π12 +φ= π2 ,∴φ=- π3 .则f (x )=2sin (2x- π3 ),∴f (π)=2sin (2π- π3 )=2sin (- π3 )=- √3 .故选:A .【点评】:本题主要考查由函数的部分图象求函数解析式,属于中档题.9.(单选题,4分)已知△ABC 是边长为1的等边三角形,设D ,E 分别是边AB ,BC 的中点,连接DE 并延长到点F ,使得DE=EF ,则 AF ⃗⃗⃗⃗⃗⃗•BC⃗⃗⃗⃗⃗⃗ =( ) A.0B. 14C. 18D. 58【正确答案】:B【解析】:用 AB ⃗⃗⃗⃗⃗⃗ 、 AC ⃗⃗⃗⃗⃗⃗ 表示出 AF ⃗⃗⃗⃗⃗⃗ 、 BC⃗⃗⃗⃗⃗⃗ ,再计算数量积.【解答】:解:△ABC 是边长为1的等边三角形,设D ,E 分别是边AB ,BC 的中点,连接DE 并延长到点F ,使得DE=EF ,如图,则 AF ⃗⃗⃗⃗⃗⃗•BC ⃗⃗⃗⃗⃗⃗ =( AE ⃗⃗⃗⃗⃗⃗+EF ⃗⃗⃗⃗⃗⃗ )• BC ⃗⃗⃗⃗⃗⃗ = AE ⃗⃗⃗⃗⃗⃗•BC ⃗⃗⃗⃗⃗⃗ + EF ⃗⃗⃗⃗⃗⃗•BC ⃗⃗⃗⃗⃗⃗ = DE ⃗⃗⃗⃗⃗⃗•BC ⃗⃗⃗⃗⃗⃗ = 12AC ⃗⃗⃗⃗⃗⃗•(AC ⃗⃗⃗⃗⃗⃗−AB ⃗⃗⃗⃗⃗⃗) = 12AC ⃗⃗⃗⃗⃗⃗2 - 12AC ⃗⃗⃗⃗⃗⃗•AB ⃗⃗⃗⃗⃗⃗ = 12−12×1×1×12 = 14 . 故选:B .【点评】:本题考查了平面向量的数量积运算,属于中档题.10.(单选题,4分)已知平面上的两个单位向量 a ⃗ , b ⃗⃗ 满足 a ⃗ ⋅ b ⃗⃗ = 45,若m∈R ,则| a ⃗ +m b ⃗⃗ |的最小值为( )A. 52B. 25C. 53D. 35【正确答案】:D【解析】:根据条件及 |a ⃗+mb ⃗⃗|=√(a ⃗+mb ⃗⃗)2进行数量积的运算即可得出 |a ⃗+mb⃗⃗|=√m 2+85m +1 ,然后配方即可求出最小值.【解答】:解:∵ |a ⃗|=|b ⃗⃗|=1,a ⃗•b ⃗⃗=45, ∴ |a ⃗+mb ⃗⃗|=√(a ⃗+mb ⃗⃗)2 = √a ⃗2+2ma ⃗•b ⃗⃗+m 2b ⃗⃗2 = √m 2+85m +1 = √(m +45)2+925, ∴ m =−45 时, |a ⃗+mb ⃗⃗| 取最小值 35. 故选:D .【点评】:本题考查了单位向量的定义,向量数量积的运算,向量长度的求法,配方求二次函数最值的方法,考查了计算能力,属于中档题.11.(填空题,4分)已知i 为虚数单位,若(1+i )z=2i ,则|z|=___ .【正确答案】:[1] √2【解析】:先将z 表示出来,然后利用复数模的运算性质求解即可.【解答】:解:因为(1+i )z=2i ,所以 z =2i 1+i ,故 |z |=|2i||1+i|=√2 = √2 . 故答案为: √2 .【点评】:本题考查了复数模的求解,主要考查了复数模的运算性质的运用,考查了运算能力,属于基础题.12.(填空题,4分)已知非零向量 a ⃗ , b ⃗⃗ 满足| b ⃗⃗ |=2| a ⃗ |,且( a ⃗ + b ⃗⃗ )⊥ a ⃗ ,则 a ⃗ 与 b⃗⃗ 的夹角为___ . 【正确答案】:[1] 2π3【解析】:据题意,设 a ⃗ 与 b ⃗⃗ 的夹角为θ,| a ⃗ |=t ,则| b⃗⃗ |=2t ,由向量垂直的判断方法可得( a ⃗ + b ⃗⃗ )• a ⃗ = a ⃗2+ a ⃗ • b⃗⃗ =t 2+2t 2cosθ=0,解可得cosθ的值,即可得答案.【解答】:解:根据题意,设 a ⃗ 与 b ⃗⃗ 的夹角为θ,| a ⃗ |=t ,则| b⃗⃗ |=2t , 若( a ⃗ + b ⃗⃗ )⊥ a ⃗ ,则( a ⃗ + b ⃗⃗ )• a ⃗ = a ⃗2+ a ⃗ • b ⃗⃗ =t 2+2t 2cosθ=0,变形可得:cosθ=- 12,又由0≤θ≤π,则θ= 2π3,故答案为:2π3.【点评】:本题考查向量数量积的计算,涉及向量垂直的判断以及向量夹角的计算,属于基础题.13.(填空题,4分)在△ABC中,a= √2 b,b= √3c,则最大角的余弦值为___ .【正确答案】:[1] −√33【解析】:根据条件可得出a= √6c,从而得出A为最大角,然后根据余弦定理即可求出cosA的值.【解答】:解:∵ a=√2b,b=√3c,∴ a=√6c,∴a最大,A角最大,∴根据余弦定理,cosA=b2+c2−a22bc =2222√3c2= −√33.故答案为:−√33.【点评】:本题考查了大角对大边定理,余弦定理,考查了计算能力,属于基础题.14.(填空题,4分)已知向量a⃗,b⃗⃗是单位向量,a⃗与b⃗⃗的夹角为120°,则(a⃗ + b⃗⃗)⋅b⃗⃗=___ ,| a⃗ +2 b⃗⃗ |=___ .【正确答案】:[1] 12; [2] √3【解析】:利用向量的数量积以及向量的模的运算法则转化求解即可.【解答】:解:向量a⃗,b⃗⃗是单位向量,a⃗与b⃗⃗的夹角为120°,则(a⃗ + b⃗⃗)⋅b⃗⃗ = a⃗•b⃗⃗ + b⃗⃗2 = 1×1×(−12)+1 = 12.| a⃗ +2 b⃗⃗ |= √a⃗2+4a⃗•b⃗⃗+4b⃗⃗2 = √1+4×1×1×(−12)+4 = √3.故答案为:12;√3.【点评】:本题考查向量的数量积的求法,向量的模的运算法则的应用,是基础题.15.(填空题,4分)一艘货船以20km/h 的速度向东航行,货船在A 处看到一个灯塔P 在北偏东60°方向上,行驶4小时后,货船到达B 处,此时看到灯塔P 在北偏东15°方向上,这时船与灯塔的距离为___ km .【正确答案】:[1]40 √2【解析】:直接利用三角形内角和定理,正弦定理的应用求出结果.【解答】:解:如图所示:根据题意知:在△ABP 中,由于∠PAB=30°,∠ABP=105°,AB=80km ,所以∠P=45°,利用正弦定理: BP sin∠PAB =AB sin∠P ,整理得 BP12=√22解得BP=40 √2 .故答案为:40 √2 .【点评】:本题考查的知识要点:三角形内角和定理,正弦定理的应用,主要考查学生的运算能力和数学思维能力,属于基础题.16.(填空题,4分)梯形ABCD 中,AB || CD ,AB=2,AD=CD=1,∠BAD=90°,点P 在线段BC 上运动.(1)当点P 是线段BC 的中点时, BC ⃗⃗⃗⃗⃗⃗•AP⃗⃗⃗⃗⃗⃗ =___ ; (2) PB ⃗⃗⃗⃗⃗⃗•AP⃗⃗⃗⃗⃗⃗ 的最大值是___ . 【正确答案】:[1]-1; [2] 12【解析】:(1)根据题意,建立坐标系,求出A 、B 、C 、D 的坐标,由中点坐标公式可得P的坐标,即可得向量 BC⃗⃗⃗⃗⃗⃗ 、 AP ⃗⃗⃗⃗⃗⃗ 的坐标,由数量积的计算公式计算可得答案; (2)设P 的坐标为(m ,n ),分析m 、n 的关系,表示向量 PB ⃗⃗⃗⃗⃗⃗ 、 AP ⃗⃗⃗⃗⃗⃗ 的坐标,由数量积的计算公式可得 PB ⃗⃗⃗⃗⃗⃗•AP⃗⃗⃗⃗⃗⃗ 的表达式,由二次函数的性质分析可得答案.【解答】:解:(1)根据题意,如图,建立坐标系,则A (0,0),B (2,0),D (0,1),C (1,1),点P 是线段BC 的中点,则P ( 32 , 12 ),BC ⃗⃗⃗⃗⃗⃗ =(-1,1), AP ⃗⃗⃗⃗⃗⃗ =( 32 , 12), 则 BC ⃗⃗⃗⃗⃗⃗•AP ⃗⃗⃗⃗⃗⃗ =(-1)× 32 +1× 12=-1; (2)B (2,0),C (1,1),直线BC 的方程为x+y=2,设P 的坐标为(m ,n ),则m+n=2,(0≤n≤1),PB ⃗⃗⃗⃗⃗⃗ =(2-m ,-n ), AP⃗⃗⃗⃗⃗⃗ =(m ,n ) 则 PB ⃗⃗⃗⃗⃗⃗•AP ⃗⃗⃗⃗⃗⃗ =(2-m )m-n 2=-2n 2+2n=-2(n- 12 )2+ 12 ≤ 12 ,即 PB ⃗⃗⃗⃗⃗⃗•AP ⃗⃗⃗⃗⃗⃗ 的最大值是 12. 故答案为:(1)-1;(2) 12 .【点评】:本题考查向量数量积的计算和性质的应用,涉及,属于基础题.17.(问答题,9分)已知A (-1,2),B (3,3),C (t ,1).(Ⅰ)当A ,B ,C 三点共线时,求实数t 的值;(Ⅱ)若∠ABC=90°,求实数t 的值;(Ⅲ)当t=6时,点A ,B ,C ,D 构成平行四边形ABCD ,求点D 的坐标.【正确答案】:【解析】:(Ⅰ)分别求出 AB ⃗⃗⃗⃗⃗⃗ , BC⃗⃗⃗⃗⃗⃗ ,由A ,B ,C 三点共线,能求出t . (Ⅱ)由∠ABC=90°,得 AB ⃗⃗⃗⃗⃗⃗⊥BC⃗⃗⃗⃗⃗⃗ ,利用向量垂直的性质能求出t . (Ⅲ)当t=6时,C (6,1),平行四边形ABCD 中,设D (x ,y ),由 BA ⃗⃗⃗⃗⃗⃗ = CD ⃗⃗⃗⃗⃗⃗ ,能求出D 点坐标.【解答】:解:(Ⅰ) AB ⃗⃗⃗⃗⃗⃗ =(4,1), BC⃗⃗⃗⃗⃗⃗ =(t-3,-2), ∵A ,B ,C 三点共线,∴t -3+8=0,解得t=-5.(Ⅱ)∵∠ABC=90°,∴ AB ⃗⃗⃗⃗⃗⃗⊥BC⃗⃗⃗⃗⃗⃗ , ∴ AB ⃗⃗⃗⃗⃗⃗•BC⃗⃗⃗⃗⃗⃗ =4(t-3)+1×(-2)=0, 解得t= 72 .(Ⅲ)当t=6时,C (6,1),平行四边形ABCD 中,设D (x ,y ),由 BA⃗⃗⃗⃗⃗⃗ = CD ⃗⃗⃗⃗⃗⃗ ,得(-4,-1)=(x-6,y-1), 解得x=2,y=0,∴D (2,0).【点评】:本题考查实数值、点的坐标的求法,涉及到平面向量的坐标运算、向量共线、向量垂直、向量相等的性质等基础知识,考查运算求解能力等数学核心素养,是基础题.18.(问答题,9分)已知函数f (x )=sin 2x .(Ⅰ)求 f (π3) 的值;(Ⅱ)若 f (α)=23 ,求cos2α的值;(Ⅲ)设函数 g (x )=f (x )+√3sinxcosx ,求函数g (x )的单调递增区间.【正确答案】:【解析】:(Ⅰ)由题意根据函数的解析式,直接求得f ( π3 ) 得值.(Ⅱ)由题意用二倍角的余弦公式,计算求得结果.(Ⅲ)由题意利用三角恒等变换化简函数的解析式,再利用正弦函数的单调性求出函数g (x )的单调递增区间.【解答】:解:(Ⅰ)(1)由于函数f (x )=sin 2x ,故f ( π3 )= sin 2(π3) = 34 .(Ⅱ)若 f (α)=23 =sin 2α,∴cos2α=1-2sin 2α=- 13 .(Ⅲ)∵函数 g (x )=f (x )+√3sinxcosx =sin 2x+ √32 sin2x=1−cos2x 2 + √32 sin2x=sin (2x- π6 )+ 12 , 令2kπ- π2 ≤2x - π6 ≤2kπ+ π2 ,求得kπ- π6 ≤x≤kπ+ π3 ,求得函数g (x )的单调递增区间为[kπ- π6 ,kπ+ π3 ],k∈Z .【点评】:本题主要考查三角恒等变换,正弦函数的单调性,属于中档题.19.(问答题,9分)在△ABC 中, sinA +√3cosA =0 , a =√19 ,b=2.(Ⅰ)求A 的大小及边c 的值;(Ⅱ)若D 是BC 边上的一点,且AD⊥AC ,求△ABD 的面积.【正确答案】:【解析】:(Ⅰ)根据两角和的正弦公式求出A ,再根据余弦定理求出c 即可;(Ⅱ)根据余弦定理求出cosC ,从而求出CD ,再求出BD 的值,根据余弦定理求出cosB ,从而求出sinB ,再求出三角形的面积即可.【解答】:解:(Ⅰ)由 sinA +√3cosA =0 ,得 12 sinA+ √32 cosA=0,故sinAcos π3 +cosAsin π3 =0,故sin (A+ π3 )=0,∵A 是△ABC 的内角,∴A= 2π3 ,cosA=- 12 ,在△ABC 中,由余弦定理a 2=b 2+c 2-2bccosA ,得:19=4+c 2-4c•(- 12 ),解得:c=3或c=-5(舍),故A= 2π3 ,c=3.(Ⅱ)在△ABC 中,由余弦定理c 2=a 2+b 2-2abcosC ,得:9=19+4-4 √19 cosC ,解得:cosC= 7√1938 ,则RT△ADC中,cosC= ACCD ,解得:CD= 4√197,∴BD=BC-CD= 3√197,在△ABC中,由余弦定理b2=a2+c2-2accosB,得4=19+9-6 √19 cosB,解得:cosB= 4√1919,故sinB= √5719,∴S△ABD= 12•AB•BD•sinB= 12×3× 3√197• √5719= 9√314.【点评】:本题考查了余弦定理的应用以及求三角形的面积公式,考查转化思想,是中档题.20.(问答题,9分)在△ABC中,角A,B,C的对边分别为a,b,c,且a2+b2=√3ab+ c2.(Ⅰ)求C的值;(Ⅱ)求cosA+sinB的最大值.【正确答案】:【解析】:(Ⅰ)根据a2+b2=√3ab+c2及余弦定理即可得出cosC=√32,从而求出C=π6;(Ⅱ)可得出B= 5π6−A,从而可得出cosA+sinB=32cosA+√32sinA,然后根据两角和的正弦公式可得出cosA+sinB=√3sin(A+π3),这样即可求出cosA+sinB的最大值.【解答】:解:(Ⅰ)∵ a2+b2=√3ab+c2,∴ a2+b2−c2=√3ab,根据余弦定理,a2+b2-c2=2abcosC,∴ 2abcosC=√3ab,∴ cosC=√32,且C∈(0,π),∴ C=π6;(Ⅱ)∵ C=π6,∴ A+B=5π6,∴ B=5π6−A,∴ cosA+sinB=cosA+sin(5π6−A)= cosA+12cosA+√32sinA= 32cosA+√32sinA= √3(√32cosA+12sinA)= √3sin(A+π3),且0<A<5π6,∴ A+π3=π2,即A=π6时,cosA+sinB取最大值√3.【点评】:本题考查了余弦定理,两角和的正弦公式,正弦函数的最大值,考查了计算能力,属于中档题.。

福建省漳州第一中学2020-2021学年高一下学期期中考试数学试题 附答案

福建省漳州第一中学2020-2021学年高一下学期期中考试数学试题 附答案

漳州一中2020~2021学年第二学期期中考试高一年数学科 试卷考试时间:120分钟 满分:150分 命题:高一数学备课组一、选择题(本大题共8小题,每小题5分,共40分,在每小题给出的四个选项中,只有一项是符合题目要求的)1.已知i 为虚数单位,且复数|34|12i i z+=-,则复数z 的虚部是( ) A .103- B .103i -C .2iD .2 2.三棱台的一条侧棱所在直线与其对面所在的平面之间的关系是( )A .相交B .平行C .直线在平面内D .平行或直线在平面内3.若cos sin z i θθ=+(i 为虚数单位),则2(Z)2k k πθπ=+∈是21z =-的( ) A .充分不必要条件B .必要不充分条件C .充分必要条件D .既不充分也不必要条件4.已知圆锥的轴裁面为正三角形,且侧面积是4π,则该圆锥的高为( )AB C D .5.在ABC ∆中,2cos cos cos c bc A ac B ab C =++,则此三角形必是( )A .等边三角形B .直角三角形C .等腰三角形D .钝角三角形6.在平行四边形ABCD 中,M ,N 分别为AB ,AD 上的点,连接AC ,MN 交于点P ,已知34AM AB =且35AN AD =,若AP AC λ=,则实数λ的值为( ) A .12 B .13 C .23 D .347.古希腊数学家阿基米德是世界上公认的三位最伟大的数学家之一,其墓碑上刻着他认为最满意的一个数学发现,如图,一个“圆柱容球”的几何图形,即圆柱容器里放了一个球,该球顶天立地,四周碰边,在该图中,球的体积是圆柱体积的23,并且球的表面积也是圆柱表面积的23,若圆柱的表面积是6π,现在向圆柱和球的缝隙里注水,则最多可以注入的水的体积为( )A .2πB .43πC .πD .23π8.在ABC ∆中,2AB AC ==,BC =动点P 位于直线BC 上,当AP PB ⋅取得最大值时,向量AP 与PB 夹角的余弦值为( )A .7B .7-C .7D .7- 二、多项选择题(本大题共4小题,每小题5分,共20分.在每小题给出的四个选项中,有多项符合题目要求。

山东省泰安第一中学2020-2021学年高一下学期期中考试英语试题

山东省泰安第一中学2020-2021学年高一下学期期中考试英语试题

山东省泰安第一中学2020-2021学年高一下学期期中考试英语试题学校:___________姓名:___________班级:___________考号:___________一、阅读选择Ninety-five percent of American families are now online, with adults spending averagely five hours a day at home on the computer, which greatly influences their life, according to a new study. Yes, we’re connecting more with friends, but we’re also having dinner quickly so we can update our Facebook status. Does your life suffer from too much time spent online, and do you properly protect your fam ily’s identity when you share their information online? Here’s how to take control of them.According to Sherry Turkle, professor of psychology at MIT, many people use their computers to avoid the messiness of real life. It’s difficult to refuse a friend, but it’s easy to send out an e-mail to do that. When you find yourself hiding behind your screen, make an effort to reconnect with people face to face. “It’s not because the technology is bad,” says Turkle. “It’s a matter of figuring out its place.”Proud parents can’t help posting photos of their kids. But publicly sharing your kids’ information, such as your child’s full name, birth date, and place of residence could put him in danger. To avoid the risk, invite the people you know well to view the photos onpassword-protected (加密的) websites such as Flickr and Snapfish. If you use Facebook, create a group of your inner circle specially for sharing photos and news of your kids.Need a handy way to measure your family’s online habits? Check out the family pla n on rescuetime. com. It tracks how each member of your family spends time online, and it shows the data by hour, day, and week. The website, which also offers personal plans, even allows you to block distracting (分心的) websites from your loved ones and yourself.If reaching for your phone to check for messages and e-mails has become an uncontrollable habit, try this trick. Keep your devices on but turn off every message reminding, vibration (振动), and so on. Check for updates only when you finish a task.1.Sherry Turkle probably agrees that ________.A.Internet is just a tool for peopleB.people have to know their social statusC.technology can help improve friendshipD.going online helps people lead a happier life2.How are family members’ online habits trac ked by ?A.By offering plans and blocking unsafe websites.B.By blocking unwanted contact and information.C.By tracking their online time and sorting out data.D.By making plans and storing collected data.3.What can be the best title for the text?A.Important Tips on Protecting Online InformationB.How to Take Control of Families’ Technology TimeC.Key Advice on How to Avoid Unsafe WebsitesD.How to Break Away from Bad Online HabitsMy name is Sara. When I was little, I played the drums. I also had a guitar. In fourth grade, I started playing the trombone (长号). I practised about four hours a week. All of this might not seem like a big deal for a lot of kids, but there's something about me that makes me a bit different from others. I was born without hands. Since I was about one year old, I’ve worn prosthetics (假肢).This year, I got an invitation to join the high school marching band (行进管乐队). I told my mom I wanted to do it. But I had an instructor who thought I would not be able to march in the band — not because it was a high school band and I was only in seventh grade, but probably because my body was different. All I wanted was to show that I could do it, so I joined the band. And it paid off!Music gives me energy. That happens sometimes. One time I was so down, I didn’t even want to get out of bed. Then I hit my MP3 player by accident. A song came on, and I got up and started dancing. It helped me say to myself, “OK, I can get through today.”Around my musician friends, we all share the same problems, like working out how many beats there are in a measure (小节). I have a hard time counting the beats, but so do a lot of the other kids. It’s a normal problem that we musicians share. When I’m with the band, I don’t feel as different as I do in other situations. It’s just another way that music makes me want to go on,and not to just sit down by myself and not care about life.4.In what way is Sara different from other kids?A.There’s something wrong with her body.B.She knows how to play many instruments. C.She learned to play the drums at a very early age. D.She kept playing the trombone for the longest hours.5.When invited to join the marching band, Sara________.A.said no at first B.had no idea what to doC.followed the instructor’s advice D.believed that she would make it 6.How does Sara probably feel when she’s with the band?A.Bored. B.Relaxed.C.Successful. D.Afraid.7.What would be the best title for the text?A.A High School Band B.A Young DrummerC.My Love for Music D.My Magic HandsNo doubt there are ups and downs in life. Whatever the situation is, you shouldn’t lose your joy of life. Life is for a limited period only and no one knows how long he/she will live, so why do you waste your precious time in worrying about the things that are beyond your control? Be happy, and enjoy your life unconditionally (无条件地).You enjoy good days but you also need to learn how to enjoy bad days, even enjoy your pain. In 2016 when I was in Geneva, Switzerland, I suffered a sudden heart attack. My colleagues called an ambulance and I was taken to hospital with much pain in my chest. Before reaching hospital, I was totally exhausted with pain and was going to lose control of my emotions. Then the doctor in the ambulance said, “Don’t worry; you are in safe hands.” His words took away all my pain because I started realizing that it was no time to worry about pain and it’s time to be happy that my life was safe. At that time, I learnt an important lesson that in pain there is a hidden joy and whoever sees the bright side can enjoy pain. My pain turned into a joy which greatly helped me recover more quickly than expected.You not only enjoy success but you also need to learn to enjoy failure. Failure provides you with an opportunity to benefit from so many choices you’ve made. Celebrating failure will raise your morale and make you more powerful and determined to achieve success. We all make mistakes in life but only the courageous (勇敢的) people not only laugh at their ownmistakes but also let other people laugh at them and then they reach success without any spiritual burden (负担). A person who learns from mistakes and knows how to turn the bad situation into his/her favor is the most intelligent person and really enjoys his/her life. 8.What does the author mainly tell us in the first paragraph?A.Life is full of ups and downs. B.People’s lives only last a limited period. C.We should enjoy our life unconditionally. D.Bad situations can be changed into good ones.9.Why did the author still feel happy when experiencing much pain?A.His colleagues were always with him.B.He could be looked after by his parents.C.He planned to enjoy the last days in life.D.His doctor made him realize the value of being alive.10.The underlined word “morale” in Paragraph 3 is closest in meaning to “________”. A.talent B.confidenceC.pleasure D.inspiration11.The author thinks that the wisest person________.A.never laughs at others B.has strong determinationC.is ready to do others a favor D.is good at learning from mistakesThere’s no doubt that one of the greatest human achievements is the exploration of the space. Ever since astronaut Yuri Gagarin became the first person to be sent into the orbit around the moon in 1961, scientists have been pushing the boundaries further and further. But until now the exploration into the unknown has been dominated (主导) by men.Of course, in the past, women were also included in the space projects and played an active role on the ground and behind the scenes. For example, they worked as seamstresses (女裁缝师), sewing vital spaceflight components. In fact, many of NASA’s key works would never have been possible without them. Recently Hollywood produced a movie called Hidden Figures to focus on a group of American female mathematicians, especially the black women, who helped NASA send the first American into space. But this was not women’s only contribution. Back in 1963, Soviet astronaut Valentina Tereshkova became the first woman to be sent into space. However, after that, space flight programs were slow to employ women. In the USA.NASA didn’t accept applications from women to become astronauts until 1978.But attitudes have changed and leading officials at NASA say that the first person to set foot on Mars should be a woman. The space agency aims to have a sex-balanced workforce but can only achieve that if equal numbers of men and women are trained for science and technology jobs. As Allison McIntryre told the BBC, “My director is a woman. We have female astronauts. We haven’t put a woman on the moon yet. And I think that perhaps the first person to step on Mars should be a woman.”12.What did Yuri Gagarin do in 1961?A.He landed on the moon in success.B.He discovered many new boundaries.C.He led scientists to explore the moon.D.He made the first journey into the space.13.Why does the author mention the film Hidden Figures?A.To show women are the true heroes of NASA’s first launch.B.To stress that black people have won equal rights in NASA.C.To prove women can do as well as men in NASA’ projects.D.To present women’s contributions to NASA’s space programs.14.What is Allison McIntryre’s attitude toward women astronauts?A.Uncaring. B.Disapproving.C.Supportive. D.Disappointed.15.What is the best title for the text?A.Will the First Person to Step on Mars Be a Woman?B.Great Achievements Have Been Made in Space Exploration?C.Why Men Played an Important Role in Exploring the Unknown?D.Men and Women Have Made Equal Contributions to NASA’s Projects?二、七选五Whether you are on top of the world or feel you are holding it up, we all need help sometimes. Here are four ways to get to a better place.Pay attention inside.16.It is the small voice, the feeling in your heart. If you are really listening, you will hear what is right and what is wrong to do. You’ll know better how to take steps to change.17.Setting aside peaceful time allows you to get your mind clear. Then you can go on to build great things. So pick a place, make it regular, and bring peace to your mind.Speak with someone you don’t know.Sometimes you need to take a practical step beyond yourself. A number of nonprofits (非营利组织) provide a listening ear. Sidewalk Talk is a great one. 18.You can stop by and talk, opening your heart and sharing your worries.Get out in nature.19.Try being a tourist in your hometown. I am sure there is something peaceful to see.Relaxing outings help you rise far above your latest worry or self-doubt. Nature can lift you higher.Sometimes we can give to others. 20.I hope these tips will help you out of the depths and reach higher heights.A.List your thankfulness.B.Fill your mind with peace.C.Sometimes we need a helping hand.D.Being a listening ear makes us feel valued.E.Caring people set up a space on the sidewalk.F.If you’re looking for somewhere to start, it is within you.G.There’re few things as comforting as being a part of our nature.三、完形填空My former teacher, Katelyn Varga, was an amazing teacher. The first day I had her social studies class, I knew we would have a great 21 . Her style of teaching was so 22 that almost every student of hers loved studying social studies.My favorite 23 was from our class about the American Civil War. Each student 24 a person from the American Civil War to 25 and then explained his or her findings in class. I chose Abraham Lincoln while other classmates chose other 26 people of the time like Jefferson Davis. The students would walk around 27 about the other students’ characters and their 28 in the tragic time period. Mrs. Varga could always find useful ways to make her students well 29 while they have 30 at the same time. Besides, she always 31 us to explore new things.To be honest, Mrs. Varga has a great 32 on me. I remember I 33 badlybefore. 34 , I met Mrs. Varga and she made me become the best student that I could be.I really appreciate her coming to our school. During my eighth-grade year when I was 35 where to go to high school, she was one of the biggest reasons I continued to 36Conrad Schools of Science. The last day of school was a(n) 37 one for us, because she would no longer teach me. 38 our graduation ceremony was over, I went to her room to say my final goodbyes. Mrs. Varga gave me a big hug. 39 of us stood there crying in each other’s arms.Mrs. Varga is one of the best teachers that I have ever had. She pours everything she has into her 40 . Thanks to Mrs. Varga, I had a great time at Conrad Schools of Science. 21.A.dream B.relationship C.membership D.opportunity 22.A.interesting B.disappointing C.traditional D.uncertain 23.A.experiment B.medal C.course D.memory 24.A.judged B.described C.picked D.drew 25.A.imagine B.praise C.repeat D.research 26.A.nice B.famous C.strange D.white 27.A.learning B.wondering C.caring D.worrying 28.A.habits B.partners C.roles D.expectations 29.A.dressed B.prepared C.understood D.taught 30.A.fun B.pressure C.courage D.patience 31.A.persuaded B.encouraged C.promised D.invited 32.A.impression B.pity C.influence D.opinion 33.A.sang B.pronounced C.felt D.behaved 34.A.Suddenly B.Luckily C.Undoubtedly D.Surprisingly 35.A.considering B.asking C.checking D.introducing 36.A.appreciate B.visit C.choose D.respect 37.A.embarrassing B.hard C.amazing D.frustrating 38.A.Although B.Once C.Before D.After 39.A.Both B.None C.Any D.All 40.A.family B.children C.job D.studies四、用单词的适当形式完成短文阅读下面短文,在空白处填入1个适当的单词或括号内单词的正确形式。

【原创新高考】2020-2021学年度下学期高一第一次月考卷 英语试卷 (A)(含答案)

【原创新高考】2020-2021学年度下学期高一第一次月考卷   英语试卷 (A)(含答案)

1【原创新高考】2020-2021学年度下学期高一第一次月考卷英 语 (A )注意事项:1.答题前,先将自己的姓名、准考证号填写在试题卷和答题卡上,并将准考证号条形码粘贴在答题卡上的指定位置。

2.选择题的作答:每小题选出答案后,用2B 铅笔把答题卡上对应题目的答案标号涂黑,写在试题卷、草稿纸和答题卡上的非答题区域均无效。

3.非选择题的作答:用签字笔直接答在答题卡上对应的答题区域内。

写在试题卷、草稿纸和答题卡上的非答题区域均无效。

4.考试结束后,请将本试题卷和答题卡一并上交。

第一部分 阅读(共两节,满分50分)第一节(共15小题;每小题2.5分,满分37.5分)阅读下列短文,从每题所给的A 、B 、C 、D 四个选项中选出最佳选项。

AThe week -long Spring Festival holiday starting on Feb 11 is usually a busy, moneymaking movie screening season in China. It will see the release of eight movies, all domestic productions, according to the schedule already disclosed by film data platforms.Detective Chinatown 3, the newest installment in China’s well -received Detective Chinatown film franchise, topped the list of most -anticipated holiday films compiled by movie -ticketing platform Maoyan.A sequel to the 2018 comedy hit Detective Chinatown 2 that grossed 3.4 billion yuan ($526 million), Detective Chinatown 3 is set for release on the Spring Festival that falls on Feb 12. More than 3.7 million Maoyan users have expressed interest in seeing this film, according to data.The other six films to be released on the same day are the time travel comedy Hi, Mom starring popular comedians Jia Ling and Shen Teng; the mobile game -turned fantasy film The Yinyang Master that stars Chen Kun and Zhou Xun; Boonie Bears: The Wild Life , the new installment in the domestic animated comedy franchise; Assassin in Red , a fantasy thriller film based on a novel co -starring popular actress Yang Mi; New Gods: Nezha Reborn, a new animated film from Light Chaser Animation (the same production company behind the 2019 animated movie Withe Snake ); Ren Chao Xiong Yong , a comedy -drama co -starring singer and actor Andy Lau.My First Love is Eighteen Years Old , a romance movie, is set to hit theaters on Feb 14.China’s box office continued robust growth into 2021 after scoring a record high for New Year’s Day earnings. The total box office revenue in the first ten days of 2021 exceeded 2 billion yuan, up by more than 730-million -yuan year on year.The market’s total earnings in 2020 were 20.4 billion yuan. Of these, the top 10 earners were all domestic productions, according to official figures.1.How many movies are set to hit theaters during the week -long Spring Festival holiday? A .Nine. B .Eight.C .Seven.D .Six.2.Which movie can’t you watch if you are only free on Feb 12? A .Hi, Mom B .Detective Chinatown 3.C .Boonie Bears: Tire Wild Life.D .My First Love is Eighteen Years Old . 3.Who are the target readers of the text?A .The general public.B .Movie experts.C .College freshmen.D .High school students.BOver the last decade, Grandpa Ron, as the students call him, has volunteered thousands of hours every year to be with local school children—but it wasn’t until classes moved online due to COVID -19 that Ron Jacobson realized his impact. That impact reached far deeper than being a school volunteer. And those students were now missing the hugs he gave them every mornings.Back in March 2020, Jacobson had already volunteered for 900 hours during the 2019-2020 school year by the time Cle Elum -Roslyn Elementary in Ronald, Washington, closed its doors and turned to online teaching.“These kids who relied on me being there for them had suddenly lost me,” Jacobson said. “When they started doing their schoolwork online, several said that they missed Grandpa Ron.”The school received so many requests for Grandpa Ron that it added Jacobson’s email address and home address to the school’s online directory (通讯录), allowing students to keep in touch with Jacobson. Students immediately began sending Jacobson emails and letters and even coming to his home to check up on him and offer to walk his dog.Jacobson now responds to each of the students, adding a bright spot to the students’ days and his own. “I am happy to listen to the kids’ problems as well,” Jacobson said. “I have heard from school teachers and parents how much this regular communication has changed the kids’ attitudes.The Veterans of Foreign Wars has honored Jacobson—a Vietnam veteran (老兵) —by naming him a此卷只装订不密封班级 姓名 准考证号 考场号 座位号spokesman for their campaign, StillServing, which shows many ways America’s veterans continue serving even after leaving the army.“The Marine Corps taught me the two important things: finish the task and take care of your troops (军队). I’m still taking care of the troops,” Jacobson said.It’s just that they are 75 years younger than he is.4.How did the school react to the school kids’ requests?A.It sent Jacobson to visit them in person.B.It asked Jacobson to write to all of them.C.It showed every student’s email address.D.It offered Jacobson’s contact information.5.How did Jacobson feel about the online communication with the students?A.Pleased.B.Worried.C.Tired.D.Confused.6.Why was veteran Jacobson regarded a spokesman for StillServing?A.He still served in the army.B.He trained many volunteers.C.He continued to serve others.D.He encouraged kids to serve.7.What does the underlined word “they” in the last paragraph refer to?A.School teachers.B.Vietnam veterans.C.Local school kids.D.Young volunteers.CA popular saying goes, “Sticks and stones may break my bones, but words will never hurt me.” However, that’s not really true. Words have the power to build us up or tear us down. It doesn’t matter if the words come from someone else or ourselves — the positive and negative effects are just as lasting.We all talk to ourselves sometimes. We’re usually too ashamed to admit it, though. In fact, we really shouldn’t be because more and more experts believe talking to ourselves out loud is a healthy habit.This “self-talk” helps us motivate ourselves, remember things, solve problems, and calm ourselves down. Be aware, though, that as much as 77% of self-talk tends to be negative. So in order to stay positive, we should only speak words of encouragement to ourselves. We should also be quick to give ourselves a pat on the back. The next time you finish a project, do well in a test, or finally clean your room, join me in saying “Good job!”Often, words come out of our mouths without us thinking about the effect they will have. But we should be aware that our words cause certain responses in others. For example, when returning an item to a store, we might use warm, friendly language during the exchange. And the clerk will probably answer in a similar manner. Or harsh(刻薄的) and critical language will most likely cause the clerk to be defensive.Words have power because of their lasting effect. Many of us regret something we once said. And we remember unkind words said to us! Before speaking, we should always ask ourselves: Is it loving? Is it needed? If what we want to say doesn’t pass this test, then it’s better left unsaid.Words possess power: both positive and negative. Those around us receive encouragement when we speak positively. We can offer hope, build self-esteem(自尊) and motivate others to do their best. Negative words destroy all those things. Will we use our words to hurt or to heal? The choice is ours.8.What is the main idea of the first paragraph?A.Not sticks and stones but words will hurt usB.Encouraging words give us confidenceC.Negative words may let us downD.Words have a great effect on us9.Why there is no need for us to feel ashamed when we talk to ourselves?A.Almost everybody has the habit of talking to themselves.B.Talking to ourselves can has positive effect on us.C.Talking to ourselves always gives us courage.D.It does no harm to have “self-talk” when we are alone.10.What does the underlined sentence mean?A.Praise ourselves. B.Remind ourselvesC.Make ourselves relaxed. D.Give ourselves happiness11.What can we learn from the text?A.Encouraging words are sure to lead to kind offers.B.Negative words may stimulate us to make more progress.C.People tend to remember friendly words.D.It is better to think twice before talking to others.DIf you are fond of learning languages, you must start learning Chinese. English is the most widely spoken language in the world and it is a more powerful language in all fields. But it is expected thatChinese, which is one of the six official languages of the United Nations (UN), will be the most important2language in the coming years. What are the reasons behind the rapid spread of this language and why should you learn it?My desire to learn languages was the reason why I studied many Latin languages and in the process, I deepened my knowledge of the languages and literature. However, I did not feel self-sufficient (自给自足的) from this knowledge. I gained a lot of information about the Western world. But my thinking was always about Asian civilizations. I always felt I needed to learn Chinese to be a global citizen because “without learning Chinese, we see with one eye”.My contact with many international organizations and government institutions made me believe that Chinese is one of the most important languages of our time. After visiting the world’s most celebrated capitals such as Paris and London, I discovered that Chinese language can be seen everywhere in these places. In the subway in Paris, you will hear instructions in French, English and Chinese. In London, for example, the Chinese language was introduced for instruction in schools.China is an important political and economic country because it is making great economic progress that has never been seen before. The world is watching China with great surprise, and this peaceful Chinese rise makes us decide to focus on learning the Chinese language and knowing more about Chinese culture.To be a global citizen these days, I would advise you to learn Chinese. It will add more beauty to your life and allow you to better understand Chinese civilization.12.What can we learn about languages in the future according to the first paragraph?A.Some of them will disappear.B.More official languages will be added to the UN.C.English will still have an advantage over others.D.Chinese language will probably be second to none.13.What do the examples in Paragraph 3 show?A.Paris is a wonderful capital city worth a visit.B.Chinese learning is very popular in schools in London.C.People in some western countries like speaking Chinese.D.Chinese language is playing an important role in the world.14.What mainly causes Westerners to start learning Chinese according to the text?A.The rise of Chinese economy.B.Their love for language learning.C.Their curiosity about Asian culture.D.The long history of Chinese civilization.15.What could be the best title for the text?A.How to be a global citizenB.Chinese — the language you must learnC.What you should know about Chinese cultureD.Chinese economy—the most powerful engine第二节(共5小题;每小题2.5分,满分12.5分)根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。

福建省厦门市湖滨中学2020-2021学年高一下学期期中数学试题

福建省厦门市湖滨中学2020-2021学年高一下学期期中数学试题
福建省厦门市湖滨中学【最新】高一下学期期中数学试题
学校:___________姓名:___________班级:___________考号:___________
一、单选题
1.不等式 的解集是()
A. B.
C. 或 D. 且
2.已知数列 满足 , ,则数列 的前5项和 ()
A.9B.16C.25D.36
14.如图,港口A北偏东 方向的C处有一检查站,港口正东方向的B处有一轮船,距离检查站7海里,该轮船从B处沿正西方向航行3海里后到达D处观测站,已知观测站与检查站距离5海里,则此时轮船离港口A有________海里.
15.已知数列 中, , .若数列 为等差数列,则 ________.
16.已知 ,若不等式 恒成立,求 的最大值为____.
【详解】
因为 ,所以 ,所以 ,①
因为a,b,c成等比数列,所以b2=ac,由正弦定理得:sin2B=sinAsinC,②
①﹣②得: ,
化简得:4cos2B+4cosB﹣3=0,解得:cosB= 或cosB= (舍),又0<B<π,所以B= ,
①+②: , cos(A﹣C)=1,即A﹣C=0,即A=C,即三角形ABC为正三角形,
(2)设 ,若 是递增数列,求实数a的取值范围.
参考答案
1.B
【分析】
利用因式分解,结合一元二次不等式的解法求不等式.
【详解】
∵ ,∴ ,解得 ,∴不等式的解集为 .
故选:B.
【点睛】
本题主要考查一元二次不等式的解法,解集的定义,属于基础题.
2.C
【分析】
由题意可得,数列 为以1为首项以2为公差的等差数列,根据等差数列的前n项和公式计算即可.

2020-2021学年高一下学期数学期末复习卷(一)统计与概率(word版,含答案)

2020-2021学年度高一数学期末复习卷(一)——统计与概率一、单选题1.演讲比赛共有9位评委分别给出某选手的原始评分,评定该选手的成绩时,从9个原始评分中去掉1个最高分、1个最低分,得到7个有效评分.7个有效评分与9个原始评分相比,不变的数字特征是( ) A .中位数 B .平均数 C .方差 D .极差【答案】A 【分析】可不用动笔,直接得到答案,亦可采用特殊数据,特值法筛选答案. 【详解】设9位评委评分按从小到大排列为123489x x x x x x ≤≤≤≤≤.则①原始中位数为5x ,去掉最低分1x ,最高分9x ,后剩余2348x x x x ≤≤≤,中位数仍为5x ,∴A 正确. ①原始平均数1234891()9x x x x x x x =+++++,后来平均数234817x x x x x '=+++()平均数受极端值影响较大,∴x 与x '不一定相同,B 不正确 ①()()()222219119S x x x x x x ⎡⎤=-+-++-⎣⎦ ()()()222223817s x x x x x x ⎡⎤'=-'+-'++-'⎢⎥⎣⎦由①易知,C 不正确.①原极差91=x -x ,后来极差82=x -x 可能相等可能变小,D 不正确. 【点睛】本题旨在考查学生对中位数、平均数、方差、极差本质的理解.2.某单位青年、中年、老年职员的人数之比为10①8①7,从中随机抽取200名职员作为样本,若每人被抽取的概率是0.2,则该单位青年职员的人数为( ) A .280 B .320C .400D .1000【答案】C 【分析】由题意知这是一个分层抽样问题,根据青年、中年、老年职员的人数之比为1087∶∶,从中抽取200名职员作为样本,得到要从该单位青年职员中抽取的人数,根据每人被抽取的概率为0.2,得到要求的结果 【详解】由题意知这是一个分层抽样问题,青年、中年、老年职员的人数之比为1087∶∶,从中抽取200名职员作为样本, ∴要从该单位青年职员中抽取的人数为:10200801087⨯=++每人被抽取的概率为0.2,∴该单位青年职员共有804000.2= 故选C 【点睛】本题主要考查了分层抽样问题,运用计算方法求出结果即可,较为简单,属于基础题. 3.有一个人在打靶中,连续射击2次,事件“至少有1次中靶”的对立事件是( ) A .至多有1次中靶 B .2次都中靶 C .2次都不中靶D .只有1次中靶【答案】C 【分析】根据对立事件的定义可得事件“至少有1次中靶”的对立事件. 【详解】由于两个事件互为对立事件时,这两件事不能同时发生,且这两件事的和事件是一个必然事件.再由于一个人在打靶中,连续射击2次,事件“至少有1次中靶”的反面为“2次都不中靶”.故事件“至少有1次中靶”的对立事件是“2次都不中靶”, 故选:C .4.掷一枚骰子一次,设事件A :“出现偶数点”,事件B :“出现3点或6点”,则事件A ,B 的关系是A .互斥但不相互独立B .相互独立但不互斥C .互斥且相互独立D .既不相互独立也不互斥【答案】B 【详解】事件{2,4,6}A =,事件{3,6}B =,事件{6}AB =,基本事件空间{1,2,3,4,5,6}Ω=,所以()3162P A ==,()2163P B ==,()111623P AB ==⨯,即()()()P AB P A P B =,因此,事件A 与B 相互独立.当“出现6点”时,事件A ,B 同时发生,所以A ,B 不是互斥事件.故选B .5.齐王有上等、中等、下等马各一匹,田忌也有上等、中等、下等马各一匹.田忌的上等马优于齐王的中等马,劣于齐王的上等马;田忌的中等马优于齐王的下等马,劣于齐王的中等马,田忌的下等马劣于齐王的下等马.现在从双方的马匹中随机各选一匹进行一场比赛,若有优势的马一定获胜,则齐王的马获胜得概率为 A .49B .59C .23D .79【答案】C 【分析】现从双方的马匹中随机各选一匹进行一场比赛 ,列出样本空间,有9个样本点,“齐王的马获胜”包含的样本点有6个,利用古典概型概率公式可求出齐王的马获胜的概率. 【详解】设齐王上等、中等、下等马分別为,,A B C ,田忌上等、中等、下等马分别为,,a b c , 现从双方的马匹中随机各选一匹进行一场比赛,Ω={()()()()()()()()(),,,,,,,,,,,,,,,,,A a A b A c B a B b B c C a C b C c },9)(=Ωn ,因为每个样本点等可能,所以这是一个古典概型。

天津市部分区2020-2021学年高一化学下学期期中试题(含解析)

甲烷的空间充填模型为:CH3C. 普通硅酸盐水泥中加入适量石膏可以调节水泥硬化速率D. 高压输电线路使用的陶瓷绝缘材料属于硅酸盐材料【答案】A 6. 已知化学反应的能量变化曲线如图所示,下列叙述中正确的是()()()22H g +Cl g =2HCl gA. 该反应属于吸热反应B. 该反应过程中只断裂了H-H 键和Cl-Cl 键,其他化学键无变化C. 化学反应中能量变化的大小与反应物的质量多少无关D. 以上描述说明化学反应必然伴随能量变化【答案】D7. 下列事实与括号中物质的性质对应关系正确的是A. 浓硫酸与蔗糖混合后变黑(浓硫酸的吸水性)B. 浓硫酸可以用来干燥、等气体(浓硫酸的脱水性)2Cl CO C. 常温下可用铝制容器盛装浓硝酸(浓硝酸的氧化性)D. 盛放硝酸一般用棕色试剂瓶(硝酸的挥发性)【答案】C8. 不能实现下列物质间直接转化的元素是−−−−→−−−−→−−−−−→222+O +O+H O单质氧化物氧化物酸(或碱)A. S B. C. D. NSi Na【答案】B9. 用一种试剂,将、、三种物质的溶液区分开的是NaCl ()442NH SO 24Na SO A. 溶液 B.溶液C.溶液D.溶液NaOH 3AgNO 2BaCl 2Ba(OH)【答案】D10. 在恒容密闭容器中发生反应:。

下列说法能作4222CH (g)4NO (g)4NO(g)CO (g)2H O(g)+++ 为判断该反应达到化学平衡状态标志的是A. 容器内混合气体的总质量保持不变B. v 正(NO 2)=v 逆(CO 2)C. 容器内压强保持不变D. 单位时间内,消耗nmolNO 2的同时生成nmolNO 【答案】C11. 如下两个装置,一段时间后,下列叙述正确的是A. 图1装置中铜作原电池的正极,氢离子在铜表面被还原B. 图2装置中电子由锌片经导线流向铜片C. 图1装置中锌的质量减少,图2装置中锌的质量不变D. 图1装置和图2装置均可以实现化学能转化为电能【答案】A12. 在某温度下,在2L 容器中发生A 、B 两种物质间的转化反应,A 、B 物质的量随时间的变化如图所示,下列说法中正确的是A. 该反应的化学方程式为:A 2BB. 反应至时,反应达到平衡4minC. 时,正应速率大于逆反应速率8minD. 从开始至,A 的平均反应速率是4min ()0.05mol /L min ⋅【答案】DB. 该烷烃与氯气在光照时可以发生取代反应①写出X 的化学式:_______,Y 的化学式:_______②图中所示,关于转化为的反应过程,下列说法正确的是2NO 3HNO a.氮元素的化合价不发生变化b.若用与反应制取,另一种生成物可能是2NO 2H O 3HNO c.该转化过程中,既是氧化剂,又是还原剂2NO ①技术中的氧化剂为_______。

山东省潍坊市2020-2021学年高一下学期期中考试化学试题 含答案

1 试卷类型:A 潍坊市2020-2021学年高一下学期期中考试

化学 2021.5 1.答卷前,考生将自己的学校、姓名、班级、座号、准考证号等填写在答题卡和试卷指定位置. 2.回答选择题时,选出每小题答案后,用铅笔把答题卡上对应题目的答案标号涂黑.如需改动,用橡皮擦干净后,再选涂其他答案标号.回答非选择题时,将答案写在答题卡上.写在本试卷上无效. 3.考试结束后,将本试卷和答题卡一并交回. 可能用到的相对原子质量:H 1 Li 7 C 12 N 14 O 16 Na 23 S 32 Cl 35.5 Cu 64 一、选择题:本题共10小题,每小题2分,共20分.每小题只有一个选项符合题意.

1.2020年12月17日凌晨,嫦娥五号携带月壤样本成功返回地球,月壤富含3He、20Ne、21Ne、22Ne、

38Ar等核素.下列说法错误的是( )

A.3He中含有的中子数为1 B.20Ne和22Ne互为同位素

C.38Ar中含有的中子数和电子数相等 D.21Ne和38Ar的最外层电子数相等

2.下列实验中,既有离子键断裂又有共价键断裂的是( ) A.将氨气通入水中制备氨水 B.将硫酸氢钠溶于水配制溶液 C.加热熔化氯化钠固体 D.加热固态碘使其升华 3.下列关于元素周期表和元素周期律的说法正确的是( ) A.2Mg(OH)的碱性比2Be(OH)

的弱

B.在过渡元素中寻找优良的催化剂 C.第3周期主族元素的简单离子半径从左到右依次减小 D.最外层电子数为2的短周期元素一定是ⅡA族元素 4.土壤中的微生物可将大气中2HS

转化成24HSO,其反应能量变化如图所示.下列说法正确的是( ) 2

A.上述反应属于吸热反应 B.反应中共价键断裂的同时既形成离子键又形成共价键 C.21mol HS(g)和22mol O(g)

的总能量比241mol SO(aq)和2mol H(aq)的总能量高

D.反应物化学键断裂吸收的能量比生成物化学键形成放出的能量多 5.W、X、Y、Z均为短周期主族元素,且原子序数依次增大.W最外层电子数是次外层电子数的3倍,Y与W同主族,在短周期中X原子的失电子能力最强.下列说法错误的是( ) A.2XY

2020-2021学年陕西省汉中市高一下学期期中联考生物试题

2020-2021学年陕西省汉中市高一下学期期中联考生物试题1. 2020年11月28日,“奋斗者”号完成万米深潜海试验任务并顺利返航,体现了我国自主研发深海装备技术的突破和进步。

潜水器在深海发现了水滴鱼、盲虾等,还有大量的微生物。

下列相关分析错误的是()A.水滴鱼细胞中的RNA主要位于细胞质中B.盲虾细胞内含有自由水和结合水C.盲虾细胞中含量最多的有机物是蛋白质D.水滴鱼细胞膜中主要成分是脂肪和蛋白质2.如图①~④为几种细胞器的示意图,下列叙述错误的是()A.叶片表皮细胞不能同时找到①②③④四种细胞器B.在高倍光学显微镜下观察不到①③的双层膜结构C.①和③可以发生能量的转换,②和④进行脂质的合成D.分泌淀粉酶的唾液腺细胞中的②④比肌细胞的多3.人肝细胞合成的脂肪以VLDL(脂肪与蛋白质复合物)形式分泌出细胞外。

VLDL分泌出细胞外的方式是()A.自由扩散B.协助扩散C.主动运输D.胞吐4.如图为生物体内葡萄糖分解代谢过程的图解。

下列有关说法正确的是()A.葡萄糖在线粒体中经过程①②彻底氧化分解B.在②反应过程中,水和[H]既是产物又是反应物C.无氧条件下,发生在酵母菌细胞中的是过程③D.无氧呼吸产生ATP较少,原因是大部分能量以热能形式散失5.多细胞生物的生长,除了依靠细胞数目的增多,还依靠细胞体积的增大。

下列关于细胞体积的说法正确的是()A.不同生物细胞体积大小相差很大B.细胞体积越大相对表面积越大,物质运输效率越低C.细胞越小越有利于与外界的物质交换,因此细胞越小越好D.细胞不能无限长大的原因之一是细胞核能控制的范围是有限的6.下图表示连续分裂细胞的两个相邻的细胞周期。

下列相关叙述错误的是()A.a+b、c+d可分别表示一个细胞周期B.同种生物不同细胞的c段时间都是相同的C.b段主要完成染色体的平均分配D.a和c段结束,DNA含量增加一倍7.依据细胞生理特点鉴别一个正在进行有丝分裂的细胞是植物细胞还是动物细胞,最可靠的方法是检查它的A.DNA自我复制的方式B.是否出现星射线C.细胞质分成两部分的方式D.自身的蛋白质合成的方式8.关于“观察根尖分生组织细胞的有丝分裂”实验的叙述,错误的是()A.盐酸能够破坏细胞间的果胶,使根尖细胞容易被分开B.染色后用清水漂洗根尖的目的是洗去浮色便于观察C.压片有利于使根尖分生区细胞分散开D.视野内不会看到某个细胞分裂的连续变化过程9.细胞分化是生物界普遍存在的一种生命现象,下列叙述不正确的是()A.造血干细胞分化形成白细胞的过程是可逆的B.老年人体内仍然存在着具有分裂和分化能力的细胞C.分化后的不同组织细胞中蛋白质种类不同D.植物器官的形成是细胞分裂和细胞分化的结果10.与个体衰老一样,细胞衰老会表现出明显的特征。

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金山中学2017学年度第二学期高一年级信息学科期中考试卷(考试时间:60分钟满分:100分)第一部分基础知识部分一、选择题(每题2分)1.“什么是信息?”信息论作者认为“信息是能消除不确定性的东西。

”他是()A.比尔·盖茨 B.冯·诺依曼 C.阿兰·图灵 D. 克劳德·香农2.(110)10 + (110)2的运算结果是()。

A.(1100100)2 B.(110110)2 C.(E9)16 D.(74)163.对于用五笔输入法输入的汉字“算”,和用拼音输入法输入的汉字“算”来说,以下说法正确的是()。

A.它们的输入码相同,机内码不同B.它们的输入码不同,机内码相同C.它们的输入码和机内码都相同D.它们的输入码和机内码都不同4.存放一个24点阵汉字字形码,需要的字节数是()A.596 B. 3 C.72 D.1925.图像数字化与声音数字化都需要通过“采样”和“量化”两个步骤。

甲认为:把图像按照行列分割成若干个像素的过程,相当于声音数字化中的“采样”;乙认为:将图像中每个像素记录为若干个二进制位数,相当于声音数字化中的“量化”。

你认为()。

A.甲同学和乙同学的说法都正确B.甲同学的说法正确,乙同学的说法错误C.甲同学的说法错误,乙同学的说法正确D.甲同学和乙同学的说法都错误6.如图所示,图片A与图片B均为BMP格式的位图文件,且分辨率及每种颜色量化的二进制位数相同。

现将两幅图片分别在画图板中打开并另存为JPG格式,以下关于两幅图片格式转换数据量大小的说法正确的是()。

图片A 图片BA.图片A较大,因为图中海豚的个头比图片B大B.图片B较大,因为图中的海豚个数比图片A多C.图片B较大,因为图中的颜色变化比图片A多D.图片A与图片B一样大,因为分辨率及每种颜色量化的二进制位数相同7.小张正在调试自己的VB程序,在单击“运行”按钮后,运算结果成功地显示在屏幕上,则屏幕上显示的运算结果其数据来源是()。

A.控制器 B.运算器 C.内存储器 D.显示器8.华为推出了一款新手机,该手机标配存储容量64GB。

请问1GB容量可以存放()英文字母?A.1024 * 1024 * 1024 B. 1024 * 1024C.1024 * 1024 * 1024/8 D. 1024 * 1024 *1024 * 89.以下软件中,属于系统软件的是()。

A.金山毒霸B.PowerPointC.Windows Media Player D.Linux10.某人的不幸遭遇通过微博的传播引起了广泛的关注,接着,有微博提议对该人进行捐助,并提供了收款的账号。

面对这种情况,有人担心事情本身的真假,有人则担心捐款的真假。

合理的思考是()。

A. 若事情本身是真的,捐款也是真的B. 不论如何,全当假的看待C. 即使事情本身是真的,捐款也有可能是假的D. 原来相信事情本身是真的,但听说要捐款后,认为两者都是假的11.组成计算机网络的三要素是计算机设备、通信线路和连接设备、网络协议。

关于网络三要素,以下说法正确的是()。

A.通信线路必须是网线B.目前最常用的连接设备是集线器C.网络协议就是计算机之间进行数据通信的规则D.计算机设备必须是计算机,不能是手机、pad等移动设备12.通常楼宇内的有线通信线路使用双绞线,布线汇聚点在楼宇的中间楼层,最主要的原因是()。

A.汇聚点放在中间楼层布线方便B.避免因线路过长导致信号衰减C.汇聚点放在中间楼层便于管理D.提高网络安全性能13.以下哪一种协议通过在传输前建立连接;传输时,由于数据丢失或有差错而未收到接收方的确认信息,发送方将重新发送该数据分组。

由此实现数据的可靠传输的协议是()A.IP B.TCP C.UDP D.DNS14.学校机房的通常上网方式是()。

A.整个局域网通过无线接入因特网B.整个局域网通过路由器接入因特网C.每个电脑通过各自的ADSL线路接入因特网D.每个电脑通过各自的有线通线路接入因特网15.某公司网络中一台电脑的IP地址为11000000 10101000 00000000 00000010,理论上该公司的这个网络中可以包含主机数量最多是()。

A.192个 B.255个 C.254个 D.255个16.小王同学参加社会实践活动后,将活动的照片存储到了自己的网盘中供同学们下载。

他将照片上传到网盘中的最主要目的是()。

A.数据通信 B.资源共享 C.分布式处理 D.信息安全17.小王家的电信宽带提供的下行速度是100Mbps,上行速度是10Mbps,他有10MB的照片要传到网盘中,理论上他最少需要的时间()。

A.1秒 B.8秒 C.10秒 D.80秒18.小王收到了一条95555的短信,说其招商银行的积分即将过期,具体请登录http://1c1ImOHa进行兑换,小王确认95555是招商银行的客服电话,对于这条信息,小王正确的做法是()。

A.打电话与招商银行客服联系确认B.迅速用手机点开访问链接,以防积分过期失效C.将此信息转发给更多的同学,与好朋友分享D.将此信息转发给同学小玲,让小玲试过后再兑换19.《易传》记录“易有太极,始生两仪。

两仪生四象,四象生八卦”。

八卦,由阳爻(yáo)“—”和阴爻“- -”两个元素构成,共有:“乾☰”、“兑☱”、“离☲”、“震☳”、“巽(x ùn)☴”、“坎☵”、“艮(gèn)☶”、“坤☷”这八个卦象。

如果按下图的规则对每个卦象进行编码,则“兑☱”的二进制编码是()。

A.001 B.110 C.100 D.01120.2017年5月27日,继前两战失利之后,2017年人机大战三番棋第三局结束,柯洁执白209手中盘负于AlphaGo。

至此,柯洁九段与围棋人工智能AlphaGo的人机大战结局被定格在了0:3。

Alpha Go利用基于人工神经网络的深度学习算法,判断出在当前规则内对自己最有利的步骤,从而将计算量控制在计算机可以完成的范围内。

科学家将围棋专家们的比赛记录输入给Alpha Go,并让其自己进行学习训练,某种程度上讲,Alpha Go的围棋本领是自学成才。

根据以上描述,下列说法最合理的是()。

A.Alpha Go这类神经网络学习算法只能下围棋B.制作Alpha Go人工智能程序的研究人员下围棋水平必须很高C.Alpha Go采用的是穷举所有人机对战步骤并挑选合适的步骤下子D.人工智能不受疲劳、情绪等因素影响,在某些领域应用比人类更有优势二、计算题,在答题纸上写出计算过程,直接书写答案不得分。

(2+2+3+3分)21.(205)10=( )222.(1011001)2=( )1623.现有1个256色GIF位图文件,宽600像素,高500像素,求未压缩数据量(字节)。

24.小明用录音软件录制了一段双声道立体声音频,16bit量化,采样频率为44.1KHz,音频时长1分钟,若这段音频用未压缩方式的WAV文件格式保存,求数据量最少为多少字节。

第二部分算法和程序设计常用函数: 1. 求算术平方根 sqr() 2. 求绝对值 abs() 3. 向下取整 int()除注明分值各题,其余每题2分,共50分。

25.当X分别为0,6时,表达式X<5 or X>=6 and not (X>=6)的值分别为()。

A.true,false B.true,trueC.false,true D.false,false26.下列描述算法的流程图符号中,如果要对“b=a+c”这一条件进行判断,应使用的流程图符号是( )。

A B CD27. 现有数组d 如下:若按降序排列,采用选择排序算法选出最大值进行比较和交换,那么在第4轮的数据处理过程后,d(8)的值是( )。

A .21B .6C .5D .1228. 在以下数组a 中,采用对分查找思想查找数据"all",则以下说法正确的是( )。

A .只需查找1次就能找到数据"all"B .第2次查找的范围是a(1)——a(4)C .查找过程中依次被访问到的数据是"due"、"bro"、"all"D .该数组中存放的都是字符型数据,无法使用对分查找29. 数组d 中的数据存放情况如下表,以下流程图的功能是( ) 。

并输出”Y”;若找遍所有数据后仍没找到则输出”N”。

C. 在数组d 中顺序查找10,一旦找到则输出其存储位置D. 在数组d 中顺序查找、统计10的个数并输出30. 求111291078563412+++++=s 的值,以下算法错误的是( )。

33. 写出算法执行结果输出 A 结束A ←6,B ←8,C ←3开始A ←B A > BY NA ← C A > CY N34. 写出算法执行结果x=25 y=15If x/5=int(x/5) Thenx = x + yElsey = x - xEnd If Print x , y开始 a ←”break”输出a+b 结束b ←”first”a>b输出b+aYN37. 将数学表达式aacb b x 242-+-=,写作为对应的VB 表达式38. 将浮点数型变量S 的值保留两位小数(含四舍五入),书写VB 表达式39. 小徐编写程序计算1+2+3+4+...+100的和。

但是发现他的程序不能给出正确答案。

请你帮他查找程序中错误的地方,并予以改正。

第句存在错误(2分),该句应该改为(完整书写)(2分)40.某超市进行打折促销。

单次购物总价p(单位:元)小于100时享受98折优惠,100 ≤ p < 500时享受95折优惠,500≤p时享受9折优惠。

请你补完算法流程图。

图中:①处应该填写②处应该填写41.本程序的功能是:输入一个字符串,将该字符串反向输出。

例如,输入:abcdefgh 输出:hgfedcba。

请将下列程序补充完整。

程序空白处应填写的语句是:_________________________________42.一个三位正整数,它是一个奇数,它的百位数、十位数、个位数之和为9的倍数,例如 225。

试求所有满足上述条件的数的和。

(1)我们可以用算法来完成本题。

(1分)(2)假设我们通过某一方法得到一个三位数X各位数字之和为S,如何判断S是9 的倍数?写出VB语言的关系表达式(2分)(3)用VB语言完成本题。

(4分)43.《庄子.天下篇》中写道:“一尺之棰,日取其半,万世不竭”意思是:一根一尺的木棍,如果每天截取它的一半,永远也取不完。

根据题意,第一天木棍剩下0.5尺,第二天木棍剩下0.25尺……1)在VB中处理0.25这样的小数时,应采用哪种数据类型(2分)2)编程求解,到第几天时,木棍长度小于0.01尺,写出VB代码。

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