2013年湖北文理学院专升本考试高等数学真题及答案详解
2013年高考湖北文科数学试题及答案(word解析版)6948.docx
2013年普通高等学校招生全国统一考试(湖北卷)数学(文科)一、选择题:本大题共10小题,每小题5分,共50分,在每小题给出的四个选项中,只有一项符合题目要求. (1)【2013年湖北,文1,5分】已知全集{1,2,3,4,5}U =,集合{1,2}A =,{2,3,4}B =,则U B A =ð( )(A ){2} (B ){3,4} (C ){1,4,5} (D ){2,3,4,5} 【答案】B 【解析】U B A =ð{2,3,4}{3,4,5}{3,4}=,故选B .(2)【2013年湖北,文2,5分】已知π04θ<<,则双曲线1C :22221sin cos x y θθ-=与2C :22221cos sin y x θθ-=的( ) (A )实轴长相等 (B )虚轴长相等 (C )离心率相等 (D )焦距相等 【答案】D【解析】在双曲线1C :22221sin cos x y θθ-=与2C :22221cos sin y x θθ-=中,都有222sin cos 1c θθ=+=,即焦距相等,故选D .(3)【2013年湖北,文3,5分】在一次跳伞训练中,甲、乙两位学员各跳一次.设命题p 是“甲降落在指定范围”,q 是“乙降落在指定范围”,则命题“至少有一位学员没有降落在指定范围”可表示为( ) (A )()p ⌝∨()q ⌝ (B )p ∨()q ⌝ (C )()p ⌝∧()q ⌝ (D )p ∨q【答案】A【解析】因为p 是“甲降落在指定范围”,q 是“乙降落在指定范围”,则p -是“没有降落在指定范围”,q -是“乙没有降落在指定范围”,所以命题“至少有一位学员没有降落在指定范围”可表示为()p ⌝∨()q ⌝,故选A .(4)【2013年湖北,文4,5分】四名同学根据各自的样本数据研究变量,x y 之间的相关关系,并求得回归直线方程,分别得到以下四个结论:① y 与x 负相关且 2.347 6.423y x =-;② y 与x 负相关且 3.476 5.648y x =-+; ③ y 与x 正相关且 5.4378.493y x =+;④ y 与x 正相关且 4.326 4.578y x =--.其中一定不正确...的结论的序 号是( )(A )①② (B )②③ (C )③④ (D )①④ 【答案】D【解析】在①中,y 与x 不是负相关;①一定不正确;同理④也一定不正确,故选D . (5)【2013年湖北,文5,5分】小明骑车上学,开始时匀速行驶,途中因交通堵塞停留了一段时间,后为了赶时间加快速度行驶,与以上事件吻合得最好的图像是( )(A ) (B ) (C ) (D )【答案】C【解析】可以将小明骑车上学的行程分为三段,第一段是匀速行驶,运动方程是一次函数,即小明距学校的距离是他骑行时间的一次函数,所对应的函数图象是一条直线段,由此可以判断A 是错误的;第二段因交通拥堵停留了一段时间,这段时间内小明距学校的距离没有改变,即小明距学校的距离是行驶时间的常值函数,所对应的函数图象是平行于x 轴的一条线段,由此可以排除D ;第三段小明为了赶时间加快速度行驶,即小明在第三段的行驶速度大于第一段的行驶速度,所以第三段所对应的函数图象不与第一段的平行,从而排除B ,故选C .(6)【2013年湖北,文6,5分】将函数sin ()y x x x =+∈R 的图象向左平移(0)m m >个单位长度后,所得到的图象关于y 轴对称,则m 的最小值是( )(A )π12 (B )π6 (C )π3 (D )5π6【答案】B【解析】因为sin ()y x x x +∈R 可化为2cos()6y x π=-(x ∈R ),将它向左平移π6个单位得x x y cos 26)6(cos 2=⎥⎦⎤⎢⎣⎡-+=ππ,其图像关于y 轴对称,故选B .(7)【2013年湖北,文7,5分】已知点(1,1)A -、(1,2)B 、(2,1)C --、(3,4)D ,则向量AB 在CD 方向上的投影为( )(A(B(C) (D)【答案】A【解析】2,1AB =(),5,5CD =(),则向量AB 在向量CD方向上的射影为cos AB CD ABCD θ⋅==2==,故选A . (8)【2013年湖北,文8,5分】x 为实数,[]x 表示不超过x 的最大整数,则函数()[]f x x x =-在R 上为( )(A )奇函数 (B )偶函数 (C )增函数 (D )周期函数 【答案】D【解析】函数()[]f x x x =-表示实数x 的小数部分,有(1)1[1][]()f x x x x x f x +=+-+=-=,所以函数()[]f x x x =-是以1为周期的周期函数,故选D .(9)【2013年湖北,文9,5分】某旅行社租用A 、B 两种型号的客车安排900名客人旅行,A 、B 两种车辆的载客量分别为36人和60人,租金分别为1600元/辆和2400元/辆,旅行社要求租车总数不超过21辆,且B 型车不多于A 型车7辆.则租金最少为( )(A )31200元 (B )36000元 (C )36800元 (D )38400元 【答案】C【解析】根据已知,设需要A 型车x 辆,B 型车y 辆,则根据题设,有2170,03660900x y y x x y x y +≤⎧⎪-≤⎪⎨>>⎪⎪+=⎩, 画出可行域,求出三个顶点的坐标分别为4(7)1A ,,2(5)1B ,,6(15C ,),目标函数 (租金)为16002400k x y =+,如图所示.将点B 的坐标代入其中,即得租金的最小值为:1600524001236k =⨯+⨯=(元),故选C . (10)【2013年湖北,文10,5分】已知函数()(ln )f x x x ax =-有两个极值点,则实数a 的取值范围是( )(A )(,0)-∞ (B )1(0,)2(C )(0,1) (D )(0,)+∞【答案】B【解析】'()ln 12f x x ax =+-,由()(ln )f x x x ax =-由两个极值点,得'()0f x =有两个不等的实数解,即ln 21x ax =-有两个实数解,从而直线21y ax =-与曲线ln y x =有两个交点. 过点01(,-)作ln y x =的切线,设切点为00x y (,),则切线的斜率01k x =,切线方程为011y x x =-. 切点在切线上,则00010x y x =-=,又切点在曲线ln y x =上,则00ln 01x x =⇒=,即切点为10(,).切线方程为1y x =-. 再由直线21y ax =-与曲线ln y x =有两个交点,知直线21y ax =-位于两直线0y =和1y x =-之间,如图所示,其斜率2a 满足:021a <<,解得102a<<,故选B .二、填空题:共7小题,每小题5分,共35分.请将答案填在答题卡对应题号的位置上...........答错位置,书写不清,模棱两可均不得分.(11)【2013年湖北,文11,5分】i 为虚数单位,设复数1z ,2z 在复平面内对应的点关于原点对称,若123i z =-,则2z = . 【答案】23i -+【解析】复数123i z =-在复平面内的对应点123Z -(,),它关于原点的对称点2Z 为2,3-(),所对应的复数为223i z =-+.(12)【2013年湖北,文12,5分】某学员在一次射击测试中射靶10次,命中环数如下:7,8,7,9,5,4,9,10,7,4则(1)平均命中环数为 ;(2)命中环数的标准差为 .【答案】(1)7;(2)2【解析】(1)()178795491074710+++++++++=;(2)2s ==. (13)【2013年湖北,文13,5分】阅读如图所示的程序框图,运行相应的程序.若输入m 的值为2,则输出的结果i = . 【答案】4【解析】初始值2110m A B i ====,,,,第一次执行程序,得121i A B ===,,,因为A B <不成立,则第二次执行程序,得2224122i A B ==⨯==⨯=,,,还是A B <不成立,第三次执行程序, 得3428236i A B ==⨯==⨯=,,,仍是A B <不成立,第四次执行程序,得48216i A ==⨯=,,424B =⨯=,有A B <成立,输出4i =.(14)【2013年湖北,文14,5分】已知圆O :225x y +=,直线l :cos sin 1x y θθ+=(π02θ<<).设 圆O 上 到直线l 的距离等于1的点的个数为k ,则k =_________. 【答案】4【解析】这圆的圆心在原点,半径为5,圆心到直线l 1=,所以圆O 上到直线l 的距离等于1的点有4个,如图A 、B 、C 、D 所示.(15)【2013年湖北,文15,5分】在区间[2,4]-上随机地取一个数x ,若x 满足||x m ≤的概率为56,则m = .【答案】3 【解析】因为区间[2,4]-的长度为6,不等式||x m ≤的解区间为[-m ,m ] ,其区间长度为2m . 那么在区间[2,4]-上随机地取一个数x ,要使x 满足||x m ≤的概率为56,m 将区间[2,4]-分为[]2m -,和[m ,4],且两区间的长度比为5:1,所以3m =.(16)【2013年湖北,文16,5分】我国古代数学名著《数书九章》中有“天池盆测雨”题:在下雨时,用一个圆台形的天池盆接雨水. 天池盆盆口直径为二尺八寸,盆底直径为一尺二寸,盆深一尺八寸. 若盆中积水深九寸,则平地降雨量是 寸.(注:①平地降雨量等于盆中积水体积除以盆口面积;②一尺等于十寸) 【答案】3【解析】如图示天池盆的半轴截面,那么盆中积水的体积为()22961061031963V ππ=⨯++⨯=⨯(立方寸),盆口面积S =196π(平方寸),所以,平地降雨量为323196()3196⨯=寸(寸)(寸). (17)【2013年湖北,文17,5分】在平面直角坐标系中,若点(,)P x y 的坐标x ,y 均为整数,则称点P 为格点. 若一个多边形的顶点全是格点,则称该多边形为格点多边形. 格点多边形的面积记为S ,其内部的格点数记为N ,边界上的格点数记为L . 例如图中△ABC 是格点三角形,对应的1S =,0N =,4L =.(1)图中格点四边形DEFG 对应的,,S N L 分别是 ;(2)已知格点多边形的面积可表示为S aN bL c=++,其中a ,b ,c 为常数. 若某格点多边形对应的71N =,18L =, 则S = (用数值作答). 【答案】(1)3, 1, 6;(2)79【解析】(1)S=S △DFG +S △DEF =1+2=3 ,N=1,L =6.(2)根据题设△ABC 是格点三角形,对应的1S =,0N =,4L =,有 41b c += ①由(1)有63a b c ++= ② 再由格点DEF ∆中,S=2,N=0,L=6,得62b c += ③联立①②③,解得1,1, 1.2b c a ==-=所以当71N =,18L =时,171181792S =+⨯-=.三、解答题:共5题,共65分.解答应写出文字说明,演算步骤或证明过程.(18)【2013年湖北,文18,12分】在△ABC 中,角A ,B ,C 对应的边分别是a ,b ,c . 已知cos23cos()1A B C -+=. (1)求角A 的大小;(2)若△ABC 的面积S =5b =,求sin sin B C 的值. 解:(1)由cos23cos()1A B C -+=,得22cos 3cos 20A A +-=,即(2cos 1)(cos 2)0A A -+=,解得1cos 2A =或cos 2A =-(舍去).因为0πA <<,所以π3A =.(2)由11sin 22S bc A bc ====得20bc =. 又5b =,知4c =.由余弦定理得2222cos 25162021,a b c bc A =+-=+-=故a又由正弦定理得222035sin sin sin sin sin 2147b c bc B C A A A a a a =⋅==⨯=.(19)【2013年湖北,文19,13分】已知n S 是等比数列{}n a 的前n 项和,4S ,2S ,3S 成等差数列,且23418a a a ++=-.(1)求数列{}n a 的通项公式;(2)是否存在正整数n ,使得2013n S ≥?若存在,求出符合条件的所有n 的集合;若不存在,说明理由. 解:(1)设数列{}n a 的公比为q ,则10a ≠,0q ≠.由题意得243223418S S S S a a a -=-⎧⎨++=-⎩,即23211121(1)18a q a q a q a q q q ⎧--=⎪⎨++=-⎪⎩, 解得132a q =⎧⎨=-⎩,故数列{}n a 的通项公式为13(2)n n a -=-.(2)由(1)有3[1(2)]1(2)1(2)nn n S ⋅--==----.若存在n ,使得2013n S ≥,则1(2)2013n --≥,即(2)2012.n -≤-当n 为偶数时,(2)0n ->, 上式不成立;当n 为奇数时,(2)22012n n -=-≤-,即22012n ≥,则11n ≥.综上,存在符合条件的正整数n ,且所有这样的n 的集合为{21,,5}n n k k k =+∈≥N .(20)【2013年湖北,文20,13分】如图,某地质队自水平地面A ,B ,C 三处垂直向地下钻探,自A 点向下钻到A 1处发现矿藏,再继续下钻到A 2处后下面已无矿,从而得到在A 处正下方的矿层厚度为121A A d =.同样可得在B ,C 处正下方的矿层厚度分别为122B B d =,123C C d =,且123d d d <<. 过AB ,AC 的中点M ,N 且与直线2AA 平行的平面截多面体111222A B C A B C -所得的截面DEFG 为该多面体的一个中截面,其面积记为S 中. (1)证明:中截面DEFG 是梯形;(2)在△ABC 中,记BC a =,BC 边上的高为h ,面积为S . 在估测三角形ABC 区域内正下方的矿藏储量(即多面体111222A B C A B C -的体积V )时,可用近似公式V S h =⋅估中来估算.已知1231()3V d d d S =++,试判断V 估与V 的大小关系,并加以证明.解:(1)依题意12A A ⊥平面ABC ,12B B ⊥平面ABC ,12C C ⊥平面ABC ,所以A 1A 2∥B 1B 2∥C 1C 2.又121A A d =, 122B B d =,123C C d =,且123d d d <<.因此四边形1221A A B B 、1221A A C C 均是梯形.由2AA ∥平面MEFN ,2AA ⊂平面22AA B B ,且平面22AA B B平面MEFN ME =,可得AA 2∥ME ,即A 1A 2∥DE .同理可证A 1A 2∥FG ,所以DE ∥FG .又M 、N 分别为AB 、AC 的中点,则D 、E 、F 、G 分别为11A B 、22A B 、22A C 、11A C 的中点,即DE 、FG 分别为梯形1221A A B B 、1221A A C C 的中位线.因此 12121211()()22DE A A B B d d =+=+,12121311()()22FG A A C C d d =+=+,而123d d d <<,故DE FG <,所以中截面DEFG 是梯形. (2)V V <估. 证明如下:由12A A ⊥平面ABC ,MN ⊂平面ABC ,可得12A A MN ⊥.而EM ∥A 1A 2,所以EM MN ⊥,同理可得FN MN ⊥.由MN 是△ABC 的中位线,可得1122MN BC a ==即为梯形DEFG 的高,因此13121231()(2)22228DEFG d d d d a a S S d d d ++==+⋅=++中梯形,即123(2)8ahV S h d d d =⋅=++估中.又12S ah =,所以1231231()()36ahV d d d S d d d =++=++.于是1231232131()(2)[()()]6824ah ah ahV V d d d d d d d d d d -=++-++=-+-估.由123d d d <<,得210d d ->,310d d ->,故V V <估.(21)【2013年湖北,文21,13分】设0a >,0b >,已知函数()1ax bf x x +=+. (1)当a b ≠时,讨论函数()f x 的单调性;(2)当0x >时,称()f x 为a 、b 关于x 的加权平均数.(i )判断(1)f , f ,()bf a是否成等比数列,并证明()b f f a ≤; (ii )a 、b 的几何平均数记为G . 称2aba b+为a 、b 的调和平均数,记为H . 若()H f x G ≤≤,求x的取值范围.解:(1)()f x 的定义域为(,1)(1,)-∞--+∞,22(1)()()(1)(1)a x ax b a bf x x x +-+-'==++. 当a b >时,()0f x '>,函数()f x 在(,1)-∞-,(1,)-+∞上单调递增; 当a b <时,()0f x '<,函数()f x 在(,1)-∞-,(1,)-+∞上单调递减.(2)(i )(1)02a b f +=>,2()0b abf a a b=>+,0f =>.故22(1)()[)]2b a b ab f f ab f a a b +=⋅==+,即2(1)()[b f f f a =.① 所以(1),()bf f f a 成等比数列.因2a b +≥(1)f f ≥. 由①得()b f f a ≤.(ii )由(i )知()bf H a =,f G =.故由()H f x G ≤≤,得()()(b f f xf a ≤≤.② 当a b =时,()()b f f x f a a ===.这时,x 的取值范围为(0,)+∞;当a b >时,01ba<<,从而b a <,由()f x 在(0,)+∞上单调递增与②式,得b x a ≤≤即x 的取值范围为,b a ⎡⎢⎣;当a b <时,1ba>,从而b a >由()f x 在(0,)+∞上单调递减与②式,bx a ≤,即x 的取值范围为b a ⎤⎥⎦. (22)【2013年湖北,文22,14分】如图,已知椭圆1C 与2C 的中心在坐标原点O ,长轴均为MN且在x 轴上,短轴长分别为2m ,2()n m n >,过原点且不与x 轴重合的直线l 与1C ,2C 的四个交点按纵坐标从大到小依次为A ,B ,C ,D .记mnλ=,△BDM 和△ABN 的面积分别为1S 和2S .(1)当直线l 与y 轴重合时,若12S S λ=,求λ的值;(2)当λ变化时,是否存在与坐标轴不重合的直线l ,使得12S S λ=?并说明理由.解:依题意可设椭圆1C 和2C 的方程分别为1C :22221x y a m +=,2C :22221x y a n +=. 其中0a m n >>>, 1.mnλ=>(1)解法一:如图1,若直线l 与y 轴重合,即直线l 的方程为0x =,则111||||||22S BD OM a BD =⋅=,211||||||22S AB ON a AB =⋅=,所以12||||S BD S AB =. 在C 1和C 2的方程中分别令0x =,可得A y m =,B y n =,D y m =-,于是||||1||||1B D A B y y BD m n AB y y m n λλ-++===---.若12S S λ=,则11λλλ+=-,化简得2210λλ--=. 由1λ>,可解得1λ=.故当直线l 与y 轴重合时,若12S S λ=,则1λ=.解法二:如图1,若直线l 与y 轴重合,则||||||BD OB OD m n =+=+,||||||AB OA OB m n =-=-;111||||||22S BD OM a BD =⋅=,211||||||22S AB ON a AB =⋅=.所以12||1||1S BD m n S AB m n λλ++===--. 若12S S λ=,则11λλλ+=-,化简得2210λλ--=. 由1λ>,可解得1λ=. 故当直线l 与y 轴重合时,若12S S λ=,则1λ=+.(2)解法一:如图2,若存在与坐标轴不重合的直线l ,使得12S S λ=. 根据对称性,不妨设直线l :(0)y kx k =>,点(,0)M a -,(,0)N a 到直线l 的距离分别为1d ,2d ,则因为1d ==2d =12d d =. 又111||2S BD d =,221||2S AB d =,所以12||||S BD S AB λ==,即||||BD AB λ=.由对称性可知||||AB CD =,所以||||||(1)||BC BD AB AB λ=-=-,||||||(1)||AD BD AB AB λ=+=+,于是||1||1AD BC λλ+=-.① 将l 的方程分别与C 1,C 2的方程联立,可求得A x =B x = 根据对称性可知C B x x =-,D A x x =-,于是2||||2A B x AD BC x == ②1(1)λλλ+=-.③令1(1)t λλλ+=-,则由m n >,可得1t ≠,于是由③可解 得222222(1)(1)n t k a t λ-=-.因为0k ≠,所以20k >. 于是③式关于k 有解,当且仅当22222(1)0(1)n t a t λ->-, 等价于2221(1)()0t t λ--<. 由1λ>,可解得11t λ<<,即111(1)λλλλ+<<-,由1λ>,解得1λ>所以当11λ<≤+l ,使得12S S λ=;当1λ> 轴不重合的直线l 使得12S S λ=.解法二:如图2,若存在与坐标轴不重合的直线l ,使得12S S λ=. 根据对称性,不妨设直线l :(0)y kx k =>,点(,0)M a -,(,0)N a 到直线l 的距离分别为1d ,2d ,则因为1d ==,2d =12d d =. 又111||2S BD d =,221||2S AB d =,所以12||||S BD S AB λ==.因为||||A B A Bx x BD AB x x λ+===-,所以11A B x x λλ+=-.由点(,)A A A x kx ,(,)B B B x kx 分别在C 1, C 2上,可得222221A A x k x a m +=,222221B B x k x a n +=,两式相减可得22222222()0A B A B x x k x x a m λ--+=,依题意0A B x x >>,所以22AB x x >. 所以由上式解得22222222()()A B B A m x x k a x x λ-=-.因为20k >,所以由2222222()0()A B B A m x x a x x λ->-,可解得1A B x x λ<<.从而111λλλ+<<-,解得1λ>所以当11λ<≤+l ,使得12S S λ=;当1λ>l 使得12S S λ=.。
2013年湖北文理学院专升本考试考试大纲、真题
湖北文理学院2013年“专升本”考试《大学英语》样卷Part I.Listening Comprehension (20 points)Section ADirections:In this section, you will hear 10 short conversations. At the end of the each conversation, a question will be asked about what was said. Both the conversationand the question will be spoken only once. After each question there will be a pause.During the pause, you must read the four choices marked A, B, C and D, and decidewhich is the best answer. Then mark the corresponding letter on the Answer Sheetwith a single line through the center.1. A. A tourist guide.B. A travel agent.C. A receptionist.D. A clerk in a ticket office.2. A. Paul usually flies to Japan with Betty.B. Paul changed his mind at the last minute.C. Paul persuaded Betty to change her mind.D. Paul planed to go to Japan with Betty by sea.3. A. The interview is very important to her.B. She has to go through an important interview.C. She is not ready for the interview.D. The interview is probably too difficult for her to handle.4. A. In 1978. B. In 1971. C. In 1984. D. In 1985.5. A. The woman can change American dollars into RMB at any bank.B. The woman can change money at the bank next to the Peace Hotel.C. The bank next to the Peace Hotel closes early.D. Most banks do not have the service of changing money.6. A. The air quality in the city is not as serious as the woman says.B. There were no factories in the city in the past.C. The air pollution is caused by the development of industry.D. They should move to another city.7. A. In Rome. B. In Paris. C. In Madrid. D. In London.8. A. He read the newspaper.B. The woman told him.C. He listened to a radio report.D. He was told by the people in his office.9. A. He thinks pets are a lot of trouble.B. He thinks it’s not a good idea to buy a pet for Mary.C. He will probably not buy Mary a pet.D. He will discuss it again with Mary.10. A. That is looks exactly like Dianna.B. That it makes Dianna look older than she really is.C. That it makes Dianna Look prettier than she really is.D. That it makes Dianna look as beautiful as a model.Section BDirections:In this part you will hear a passage three times. When it is read for the first time you should listen carefully for its general idea. Then listen to the passage for the secondtime and fill in the blanks numbered 1 to 7 with the exact words you’ve just heard. Forblanks numbered from 8 to 10, fill in the missing information. You can either use theexact words you’ve heard or write down the main points in your own words. Finally,check your answers when the passage is read for the third time.Professional sports are very popular in the United States, and they are big 1) ____. The most popular sports are baseball, football and basketball. Each has its own season and millions of supporters. Professional teams are 2) ____ for the cities where they are 3) ____. Their strongest supporters live in these cities. When a team plays in a 4) ____ game, most people in the city follow the game with interest and 5) ____.Basketball is well known around the world. Professional basketball games in the States are played indoors during the winter months. From 6) ____ to 7) ____ one can find a professional basketball game several nights a week in most large cities.8) ________________________________________________________________________. The game is played in the evenings nearly every day of the week and on weekends as well. The season begins in April and finishes with the World Series in October.Football has become the most professional sport in the U.S. It is played on Sundays during the fall from August to January. 9) ___________________________________________________ _________________________. Both games require strength and specialized skills.Professional athletes are very well paid. 10)________________________________________ ______________________________________________________________________________.Part II. Reading Comprehension (40 points)Directions:There are 4 reading passages in this part. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C andD. You should decide on the best choice and mark the corresponding letter on theAnswer Sheet with a single line through the center.Passage OneHow do young children learn to have good values? How can parents teach their children about the importance of kindness, patience, and self-discipline? At a time when more and more parents worry about the negative and violent images (暴力形象) their children see on TV, in the movies and, on the internet, some are turning to fairy tales (童话) as a way to teach their young ones how to behave in society.Fairy tales were not always intended for children. We know this because some of these stories have existed for hundreds of years and were passed from generation to generation through songs and drama. They were considered entertainment for everyone, not only for young people. In these ancient stories, the heroes were extremely clever, fiercely independent, and never gave up. Over the years, some of the heroes’ qualities and story lines have been changed to fit the times.Psychologists think that fairy tales have a positive influence on children because they present the two sides of good and evil very clearly. When children hear the stories, they develop sympathetic for the heroic characters. In each tale, they can see that there are many different kinds of people in the world and that we all have a choice about what kind of people we want to be. We can choose to do good actions, rather than bad ones, in our lives.What kind of values can children learn from fairy tales? In “The Princess and the Pea,”a poorly dressed girl who insists she is a princess is given a difficult test by the Queen. When she passes the test, we learn that she is rewarded because she stayed true to herself. In “The Little Mermaid,” the mermaid (美人鱼) who lives under the sea longs to be with the humans on land. Through her experiences, we learn about the importance of living with and accepting other cultures. In “Pinocchio,” a wooden puppet (木偶) turns into a boy when he finally learns how to tell the truth.Teaching values is the reason most often given for teaching literature and encouraging reading. These old stories can indeed teach us lessons about human relationships that are universal (普遍的) enough to survive throughout the centuries. This might be the reason why they have been around for so long and are unlikely to disappear any time soon.1. What do we learn about fairy tales from the passage?A. They are written solely for children.B. They teach universal lessons about human relationships.C. They are all passed down through songs and drama.D. They are adapted to TV and movies as entertainment.2. Why do fairy tales have a positive influence on children?A. Good and evil are presented in a way they can easily understand.B. The characters are all good examples for them to follow.C. The heroes go through all kinds of hardships but never give up.D. There are many different kinds of characters for them to imitate.3. Some of the heroes’ qualities in fairy tales have been changed over the years______.A. to reflect the change of the valuesB. to suit the tastes of different peopleC. to arouse the interest of little childrenD. to adapt to the change of the times4. Children who have heard the story of the little mermaid might ______.A. learn to be better self-disciplinedB. be more likely to tell the truth than to tell the liesC. learn to stay true to themselves all their livesD. be better able to accept foreign cultures5. Parents encourage children to read fairy tells so that they ______.A. can entertain themselves without bothering othersB. can get to know great literature of the worldC. can stay away from violence shown on TVD. can learn how to behave in societyPassage TwoMost people think of a camel as an obedient beast of burden, because it is best known for its ability to carry heavy loads across vast stretch of desert without requiring water. In reality, the camel is considerably more than just the Arabian equivalent of the mule. It also possesses a great amount of intelligence and sensitivity.The Arabs assert that camels are so acutely aware of injustice and ill treatment that a camel owner who punishes one of the beats too harshly finds it difficult to escape the camel’s vengeance. Apparently, the animal will remember any injury and wait for an opportunity to get revenge.In order to protect themselves from the vengeful beats, Arabian camel drivers have learned to trick their camels into believing they have achieved revenge. When an Arab realizes that he has excited a camel’s rage, he places his own garments on the ground in the animal’s path. He arranges the clothing so that it appears to cover a man’s body. When the camel recognizes its master’s clothing on the ground, it seizes the pile with its teeth, shakes the garments violently and tramples(踩)on them in a rage. Eventually, after its anger had died away, the camel departs, assuming its revenge is complete. Only then does the owner of the garments come out of hiding, safe for the time being, thanks to this clever ruse(计策).6.Which of the following is mentioned in this passage?A.The camel never drinks water.B.The camel is always violent.C.The camel is always very sensitive.D.The camel is rarely used anymore.7.It is implied in the passage that ______.A.the mule is a stupid and insensitive animalB.the mule is as intelligent as the camelC.the mule is an animal widely used in the desertD.the mule is a vengeful animal8.From this passage we can conclude that ______.A.camels are generally vicious towards their ownersB.camels usually treat their owners wellC.camels don’t see very wellD.camels try to punish people who abuse them9.The writer makes the camel’s vengeful behavior clearer to the reader by presenting ______.A. a well—planned argumentB. a large variety of examplesC.some eye witness accountsD. a typical incident10.The main idea of the passage is ______.A.camels can be as intelligent as their driversB.camels, sensitive to injustice, will seek revenge on those who harm themC.camel drivers are often the target of camels’ revengeD.camels are sensitive creatures that are aware of injusticePassage ThreeToo often young people get themselves employed quite by accident, not knowing what lies in the way of opportunity for promotion, happiness and security. As a result, they are employed doing jobs that afford them little or no satisfaction. Our school leavers face so much competition that they seldom care what they do as long as they can earn a living. Some stay long at a job and learn to like it; others quite from one to another looking for something to suit them, the young graduates who leave the university look for jobs that offer a salary up to their expectation. Very few go out into the world knowing exactly what they want and realizing their own abilities. The reason behind all this confusion is that there never has been a proper vocational guidance in our educational institution. Nearly all grope(摸索) in the dark and their chief concern when they lookfor a job is to ask what salary is like. They never bother to think whether they are suited for the job or, even more important, whether the job suits them, having a job is more than merely providing yourself and your dependants with daily bread and some money for leisure and entertainment, it sets a pattern of life and, in many ways, determines social status in life, selection of friends, leisure and interest.In choosing a career you should first consider the type of work which will suit your interest. Noting is more pathetic than taking on a job in which you have no interest, for it will not only discourage your desire to succeed in life but also ruin your talents and ultimately make you an emotional wreck (受到严重伤害的人)and a bitter person.11. The reason why some people are unlikely to succeed in life is that they _____.A. have ruined their talentsB. have taken on an unsuitable jobC. think of nothing but their salaryD. are not aware of their own potential12. The difficulty in choosing a suitable job lies mainly in that_____.A. much competition has to be facedB. many employees have no working experienceC. the young people only care about how much they can earnD. schools fail to offer students appropriate vocational guidance13. Which of the following statements is most important according to the passage?A. your job must suit your interest.B. your job must set a pattern of life.C. your job must offer you a high salary.D. your job must not ruin your talents.14. The best title for this passage would be ____.A. what can a good job offerB. earning a livingC. correct attitude on job-huntingD. how to choose a job15. The word “pathetic” in paragraph 2 most probably means ____.A. splendidB. miserableC. disgustedD. touchingPassage FourNow let us look at how we read. When we read a printed text, our eyes move across a page in short, jerky movement. We recognize words usually when our eyes are still when they fixate.Each time they fixate, we see a group of words. This is known as the recognition span or the visual span. The length of time which the eyes stop—the duration of the fixation—varies considerably from person to person. It also varies within any one person according to his purpose in reading and his familiarity with the text. Furthermore, it can be affected by such factors as lighting and tiredness.Unfortunately, in the past, many reading improvement courses have concentrated too much on how our eyes move across the printed page. As a result of this misleading emphasis on the purely visual aspects of reading, numerous exercises have been devised to train the eyes to see more words at one fixation. For instance, in some exercises, words are flashed on to a screen for, say, a tenth or a twentieth of a second. One of the exercises has required students to fix their eyes on some central point, taking in the words on either side. Such word patterns are often constructed in the shape of rather steep pyramids so the reader takes in more and more words at each successive fixation. All these exercises are very clever, but it’s one thing to improve a person’s ability to see words and quite another thing to improve his ability to read a text efficiently. Reading requires the ability to understand the relationship between words. Consequently, for these reasons, many experts have now begun to question the usefulness of eye training, especially since any approach which trains a person to read isolated words and phrases would seem unlikely to help him in reading a continuous text.16. The time of the recognition span can be affected by the following facts except ________.A. o ne’s familiarity with the textB. one’s purpose in readingC. the length of a group of wordsD. lighting and tiredness17. The author may believe that reading ______.A. requires a reader to take in more words at each fixationB. requires a reader to see words more quicklyC. demands a deeply-participating mindD. demands more mind than eyes18. What does the author mean by saying “but it’s one thing to improve a person’s ability to seewords and quite another thing to improve his ability to read a text eff iciently.” in the second paragraph?A. The ability to see words is not needed when an efficient reading is conducted.B. The reading exercises mentioned can’t help to improve both the ability to see and tocomprehend words.C. The reading exercises mention ed can’t help to improve an efficient reading.D. The reading exercises mentioned has done a great job to improve one’s ability to see words.19. Which of the following is NOT true?A. The visual span is a word or a group of words we see each time.B. Many experts began to question the efficiency of eye training.C. The emphasis on the purely visual aspects is misleading.D. The eye training will help readers in reading a continuous text.20. The tune of the author in writing this article is ________.A. criticalB. neutralC. pessimisticD. optimisticPart III. Vocabulary and Structure (15 points)Directions: There are 30 incomplete sentences in this part. For each sentence there are 4 choices marked A, B, C and D. Choose the one answer that best completes the sentence. Thenmark the corresponding letter on the ANSWER P APER with a single line through thecenter.1. The noise to be just the dogs fighting for a bone in the country yard.A. made outB. worked outC. rang outD. turned out2. Our system has been designed to give the user quick and easy to the required information.A. accentB. accessC. responseD. approach3. Many young women do aerobics (增氧健美操)every day in their to achieve the perfect body.A. questB. strainC. temptationD. campaign4. The official of events is that the police were attacked and were just trying to defend themselves.A. issueB. illusionC. versionD. perspective5. If schoolchildren are allowed to work at their own , their performance will generally improve.A. versionB. paceC. evolutionD. system6. The conference was an attempt to discussion of the problem of widening gaps between the rich and the poor.A. stimulateB. conductC. intendD. uncover7. The clerk held my passport four inches from his face and to read it.A. affectedB. flippedC. strainedD. giggled8. The wounded woman got to her feet and made a at the kitchen knife at the sink.A. grabB. clickC. commentD. pat9. The professor the whole chapter, saying it was not difficult for us to study it by ourselves.A. dismissedB. coveredC. skippedD. explored10. To for the position, applicants would need to have a PhD degree and 3 years’ working experience.A. strainB. qualifyC. registerD. campaign11. Work ____ on the construction site last April and was completed within fifty-two weeks.A. varnishedB. commencedC. departed D projected12. The weed in the pool should be left untouched until the young frogs have _____.A. shapedB. departedC. soaredD. detached13. The woman and three children were now laughing and I was pleased about that, as they hadlooked _____ when I entered their house a few moments before.A. bruisedB. poisedC. scaredD. scrubbed14. Lack of Zink (锌) ____ causes a range of problems, although little scientific evidence supportsthe link.A. scarcelyB. definitelyC. appropriatelyD. supposedly15. The statistics show that those who prefer electronic banking ____ 45 percent.A. contributed toB. amounted toC. headed forD. consisted of16. He _____ the scene in front of him and immediately called in the police.A. interfered withB. broke upC. headed forD. took in17. As the shortage of skilled workers grows, the competition to _____ new employees is likely tointensify.A. recommendedB. pollC. recruitD. enroll18. He turned away for a few moments and I could see that he was _____ by the news.A. upsetB. neglectedC. overtakenD. interrupted19. Nazism _____ the dark myths of racial purity and the glories of a supposedly great history.A. fed onB. conjured upC. contributed toD. broke up20. On land, the weight of plants far _____ the weight of the animals that feed on them..A. overflowsB. affectsC. repaysD. exceeds21. Tons of food was laid out on the big table and crates of beer were ready for consumption.A. reservedB. expendedC. generatedD. stacked22. You’d better keep your leaders of your activities so that they can ensure you areadequately supported.A. informedB. amusedC. outlinedD. swallowed23. Although apparently rigid, bones exhibit a degree of elasticity that enables the skeleton to___considerable impact.A. escapeB. overwhelmC. withstandD. suppress24. Great minds generally look at life in a way to themselves.A. peculiarB. confinedC. similarD. unusual25. This is a very formal occasion. It is not appropriate to wear pants or skirts.A. messyB. franticC. casualD. jealous26. Their organization neither used nor the use of violence in its struggle for equality..A. scatteredB. enrolledC. overheadD. advocated27. Environmentalists are doing everything within their power to protect the birds and the impact of the oil spill.A. minimizeB. swallowC. exaggerateD. abridge28. Peter read the letter twice before its meaning .A. came upB. sank inC. caught onD. turned up29. When Ian was injured, Harry was chosen as a last—minute for the rugby team.A. preferenceB. diversificationC. alternativeD. replacement30. Each product by our company is quality tested at least three times, depending upon the requirements.A. derivedB. manufacturedC. demonstratedD. constructedPart IV Translation (10 points)Directions:Translate the following sentences into English.1.我认为我们在保护环境不受污染(pollution)方面还做得不够。
2013年普通高等学校招生全国统一考试湖北卷(数学理)word版含答案
2013年普通高等学校招生全国统一考试(湖北卷)数 学(理工类)一、选择题:本大题共10小题,每小题5分,共50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.在复平面内,复数2i1iz =+(i 为虚数单位)的共轭复数对应的点位于A .第一象限B .第二象限C .第三象限D .第四象限2.已知全集为R ,集合1{()1}2x A x =≤,2{680}B x x x =-+≤,则A B =R ðA .{0}x x ≤B .{24}x x ≤≤C .{024}x x x ≤<>或D .{024}x x x <≤≥或3.在一次跳伞训练中,甲、乙两位学员各跳一次.设命题p 是“甲降落在指定范围”,q 是“乙降落在指定范围”,则命题“至少有一位学员没有降落在指定范围”可表示为 A .()p ⌝∨()q ⌝ B .p ∨()q ⌝C .()p ⌝∧()q ⌝D .p ∨q4.将函数sin ()y x x x +∈R 的图象向左平移(0)m m >个单位长度后,所得到的图象关于y 轴对称,则m 的最小值是A .π12B .π6C .π3D .5π65.已知π04θ<<,则双曲线1C :22221cos sin x y θθ-=与2C :222221sin sin tan y xθθθ-=的 A .实轴长相等 B .虚轴长相等 C .焦距相等 D .离心率相等6.已知点(1,1)A -、(1,2)B 、(2,1)C --、(3,4)D ,则向量AB 在CD 方向上的投影为 ABC.D.7.一辆汽车在高速公路上行驶,由于遇到紧急情况而刹车,以速度25()731v t t t=-++(t 的单位:s ,v 的单位:m/s )行驶至停止. 在此期间汽车继续行驶的距离(单位:m )是A .125ln 5+B .11825ln 3+C .425ln 5+D .450ln 2+第8题图8.一个几何体的三视图如图所示,该几何体从上到下由四个简单几何体组成,其体积分别记为1V ,2V ,3V ,4V ,上面两个简单几何体均为旋转体,下面两个简单几何体均为多面体,则有A .1243V V V V <<<B .1324V V V V <<<C .2134V V V V <<<D .2314V V V V <<<9.如图,将一个各面都涂了油漆的正方体,切割为125个同样大小的小正方体. 经过搅拌后,从中随机取一个小正方体,记它的涂漆面数为X ,则X 的均值()E X = A .126125 B .65C .168125 D .7510.已知a 为常数,函数()(ln )f x x x ax =-有两个极值点1x ,212()x x x <,则A .1()0f x >,21()2f x >-B .1()0f x <,21()2f x <-C .1()0f x >,21()2f x <-D .1()0f x <,21()2f x >-二、填空题:本大题共6小题,考生共需作答5小题,每小题5分,共25分. 请将答案填在答题卡对应题......号.的位置上. 答错位置,书写不清,模棱两可均不得分. (一)必考题(11—14题)11.从某小区抽取100户居民进行月用电量调查,发现其用电量都在50至350度之间,频率分布直方图如图所示.(Ⅰ)直方图中x 的值为_________;(Ⅱ)在这些用户中,用电量落在区间[100,250)内的户数为_________.第11题图12.阅读如图所示的程序框图,运行相应的程序,输出的结果i =_________.第9题图14.古希腊毕达哥拉斯学派的数学家研究过各种多边形数. 如三角形数1,3,6,10, ,第n 个三角形数为2(1)11222n n n n +=+. 记第n 个k 边形数为(,)(3)N n k k ≥,以下列出 了部分k 边形数中第n 个数的表达式:三角形数 211(,3)22N n n n =+,正方形数 2(,4)N n n =,五边形数 231(,5)22N n n n =-,六边形数 2(,6)2N n n n =-, ………………………………………可以推测(,)N n k 的表达式,由此计算(10,24)N =_________.(二)选考题(请考生在第15、16两题中任选一题作答,请先在答题卡指定位置将你所选的题目序号后的方框用2B铅笔涂黑. 如果全选,则按第15题作答结果计分.)15.(选修4-1:几何证明选讲)如图,圆O 上一点C 在直径AB 上的射影为D ,点D 在半径OC 上的射影为E .若3AB AD =,则CEEO的值为_________. 16.(选修4-4:坐标系与参数方程)在直角坐标系xOy 中,椭圆C 的参数方程为cos ,sin x a y b ϕϕ=⎧⎨=⎩(ϕ为参数,0a b >>). 在极坐标系(与直角坐标系xOy 取相同的长度单位,且以原点O 为极点,以x 轴正半轴 为极轴)中,直线l 与圆O 的极坐标方程分别为πsin()4ρθ+=(m 为非零常数) 与b ρ=. 若直线l 经过椭圆C 的焦点,且与圆O 相切,则椭圆C 的离心率为_________.三、解答题:本大题共6小题,共75分. 解答应写出文字说明、证明过程或演算步骤. 17.(本小题满分12分)在△ABC 中,角A ,B ,C 对应的边分别是a ,b ,c . 已知cos23cos()1A B C -+=. (Ⅰ)求角A 的大小;(Ⅱ)若△ABC 的面积S =5b =,求sin sin B C 的值. 18.(本小题满分12分)已知等比数列{}n a 满足:23||10a a -=,123125a a a =. (Ⅰ)求数列{}n a 的通项公式;D E OBA第15题图C(Ⅱ)是否存在正整数m ,使得121111ma a a +++≥ ?若存在,求m 的最小值;若不存在,说明理由. 19.(本小题满分12分)如图,AB 是圆O 的直径,点C 是圆O 上异于,A B 的点,直线PC ⊥平面ABC ,E ,F 分别是PA ,PC 的中点.(Ⅰ)记平面BEF 与平面ABC 的交线为l ,试判断直线l 与平面PAC 的位置关系,并加以证明;(Ⅱ)设(Ⅰ)中的直线l 与圆O 的另一个交点为D ,且点Q满足12D Q C P =. 记直线PQ 与平面ABC 所成的角为θ,异面直线PQ 与EF 所成的角为α,二面角E l C --的大小为β,求证:s i n s i n s i n θαβ=.20.(本小题满分12分)假设每天从甲地去乙地的旅客人数X 是服从正态分布2(800,50)N 的随机变量. 记一天中从甲地去乙地的旅客人数不超过900的概率为0p . (Ⅰ)求0p 的值;(参考数据:若X ~2(,)N μσ,有()0.6826P X μσμσ-<≤+=,(22)0.9544P X μσμσ-<≤+=,(33)0.9974P X μσμσ-<≤+=.)(Ⅱ)某客运公司用A 、B 两种型号的车辆承担甲、乙两地间的长途客运业务,每车每天往返一次. A 、B 两种车辆的载客量分别为36人和60人,从甲地去乙地的营运成本分别为1600元/辆和2400元/辆. 公司拟组建一个不超过21辆车的客运车队,并要求B 型车不多于A 型车7辆. 若每天要以不小于0p 的概率运完从甲地去乙地的旅客,且使公司从甲地去乙地的营运成本最小,那么应配备A 型车、B 型车各多少辆?第19题图21.(本小题满分13分)如图,已知椭圆1C 与2C 的中心在坐标原点O ,长轴均为MN且在x 轴上,短轴长分别为2m ,2()n m n >,过原点且不与x 轴重合的直线l 与1C ,2C 的四个交点按纵坐标从大到小依次为A ,B ,C ,D .记mnλ=,△B D M 和△ABN 的面积分别为1S 和2S .(Ⅰ)当直线l 与y 轴重合时,若12S S λ=,求λ的值;(Ⅱ)当λ变化时,是否存在与坐标轴不重合的直线l ,使得12S S λ=?并说明理由. 22.(本小题满分14分)设n 是正整数,r 为正有理数.(Ⅰ)求函数1()(1)(1)1(1)r f x x r x x +=+-+->-的最小值;(Ⅱ)证明:1111(1)(1)11r r r r rn n n n n r r ++++--+-<<++; (Ⅲ)设x ∈R ,记x ⎡⎤⎢⎥为不小于...x 的最小整数,例如22=⎡⎤⎢⎥,π4=⎡⎤⎢⎥,312⎡⎤-=-⎢⎥⎢⎥.令S + S ⎡⎤⎢⎥的值.(参考数据:4380344.7≈,4381350.5≈,43124618.3≈,43126631.7≈)2013年普通高等学校招生全国统一考试(湖北卷)数学(理工类)试题参考答案一、选择题1.D 2.C 3.A 4.B 5.D 6.A 7.C 8.C 9.B 10.D 二、填空题11.(Ⅰ)0.0044 (Ⅱ)70 12.5 1314.1000 15.8 16三、解答题 17. (Ⅰ)由cos23cos()1A B C -+=,得22cos 3cos 20A A +-=, 即(2cos 1)(cos 2)0A A -+=,解得1cos 2A =或cos 2A =-(舍去).第21题图因为0πA <<,所以π3A =.(Ⅱ)由11sin 22S bc A bc ====得20bc =. 又5b =,知4c =. 由余弦定理得2222cos 25162021,a b c bc A =+-=+-=故a =又由正弦定理得222035sin sin sin sin sin 2147b c bc B C A A A a a a =⋅==⨯=.18.(Ⅰ)设等比数列{}n a 的公比为q ,则由已知可得331211125,||10,a q a q a q ⎧=⎪⎨-=⎪⎩ 解得15,33,a q ⎧=⎪⎨⎪=⎩ 或15,1.a q =-⎧⎨=-⎩ 故1533n n a -=⋅,或15(1)n n a -=-⋅-. (Ⅱ)若1533n n a -=⋅,则1131()53n n a -=⋅,故1{}n a 是首项为35,公比为13的等比数列,从而131[1()]191953[1()]111031013mmm n na =⋅-==⋅-<<-∑.若1(5)(1)n n a -=-⋅-,则111(1)5n n a -=--,故1{}n a 是首项为15-,公比为1-的等比数列,从而11,21(),1502().mn n m k k a m k k +=+⎧-=-∈⎪=⎨⎪=∈⎩∑N N , 故111mn n a =<∑.综上,对任何正整数m ,总有111mn na =<∑.故不存在正整数m ,使得121111ma a a +++≥ 成立.19.(Ⅰ)直线l ∥平面PAC ,证明如下:连接EF ,因为E ,F 分别是PA ,PC 的中点,所以EF ∥AC . 又EF ⊄平面ABC ,且AC ⊂平面ABC ,所以EF ∥平面ABC . 而EF ⊂平面BEF ,且平面BEF 平面ABC l =,所以EF ∥l .因为l ⊄平面PAC ,EF ⊂平面PAC ,所以直线l ∥平面PAC .(Ⅱ)(综合法)如图1,连接BD ,由(Ⅰ)可知交线l 即为直线BD ,且l ∥AC . 因为AB 是O 的直径,所以AC BC ⊥,于是l BC ⊥.已知PC ⊥平面ABC ,而l ⊂平面ABC ,所以PC l ⊥. 而PC BC C = ,所以l ⊥平面PBC .连接BE ,BF ,因为BF ⊂平面PBC ,所以l BF ⊥.故CBF ∠就是二面角E l C --的平面角,即CBF β∠=.由12DQ CP = ,作DQ ∥CP ,且12DQ CP =.连接PQ ,DF ,因为F 是CP 的中点,2CP PF =,所以DQ PF =, 从而四边形DQPF 是平行四边形,PQ ∥FD .连接CD ,因为PC ⊥平面ABC ,所以CD 是FD 在平面ABC 内的射影, 故CDF ∠就是直线PQ 与平面ABC 所成的角,即CDF θ∠=. 又BD ⊥平面PBC ,有BD BF ⊥,知BDF ∠为锐角,故BDF ∠为异面直线PQ 与EF 所成的角,即BDF α∠=, 于是在Rt △DCF ,Rt △FBD ,Rt △BCF 中,分别可得sin CF DF θ=,sin BF DF α=,sin CF BFβ=, 从而sin sin sin CF BF CFBF DF DFαβθ=⋅==,即sin sin sin θαβ=. (Ⅱ)(向量法)如图2,由12DQ CP = ,作DQ ∥CP ,且12DQ CP =.连接PQ ,EF ,BE ,BF ,BD ,由(Ⅰ)可知交线l 即为直线BD . 以点C 为原点,向量,,CA CB CP所在直线分别为,,x y z 轴,建立如图所示的空间直角坐标系,设,,2CA a CB b CP c ===,则有(0,0,0),(,0,0),(0,,0),(0,0,2),(,,)C A a B b P c Q a b c ,1(,0,),(0,0,)2E a cF c .于是1(,0,0)2FE a = ,(,,)QP a b c =-- ,(0,,)BF b c =- ,所以||cos ||||FE QP FE QP α⋅==⋅sin α=.又取平面ABC 的一个法向量为(0,0,1)=m,可得||sin ||||QP QP θ⋅==⋅ m m设平面BEF 的一个法向量为(,,)x y z =n ,所以由0,0,FE BF ⎧⋅=⎪⎨⋅=⎪⎩n n 可得10,20.ax by cz ⎧=⎪⎨⎪-+=⎩ 取(0,,)c b =n . 第19题解答图1第19题解答图2于是|||cos |||||β⋅==⋅m n m n,从而sin β==.故sin sin sin αβθ===,即sin sin sin θαβ=.20.(Ⅰ)由于随机变量X 服从正态分布2(800,50)N ,故有800μ=,50σ=(700900)0.9544P X <≤=.由正态分布的对称性,可得0(900)(800)(800900)p P X P X P X =≤=≤+<≤11(700900)0.977222P X =+<≤=. (Ⅱ)设A 型、B 型车辆的数量分别为, x y 辆,则相应的营运成本为16002400x y +.依题意, , x y 还需满足:021, 7, (3660)x y y x P X x y p +≤≤+≤+≥.由(Ⅰ)知,0(900)p P X =≤,故0(3660)P X x y p ≤+≥等价于3660900x y +≥. 于是问题等价于求满足约束条件21,7,3660900,, 0, ,x y y x x y x y x y +≤⎧⎪≤+⎪⎨+≥⎪⎪≥∈⎩N ,且使目标函数16002400z x y =+达到最小的,x y . 作可行域如图所示, 可行域的三个顶点坐标分别为(5,12), (7,14), (15,6)P Q R .由图可知,当直线16002400z x y =+经过可行域的点P 时,直线16002400z x y =+在y 轴上截距2400z 最小,即z 取得最小值.故应配备A 型车5辆、B 型车12辆.21. 依题意可设椭圆1C 和2C 的方程分别为1C :22221x y a m +=,2C :22221x y a n+=. 其中0a m n >>>, 1.m n λ=>(Ⅰ)解法1:如图1,若直线l 与y 轴重合,即直线l 的方程为0x =,则 111||||||22S BD OM a BD =⋅=,211||||||22S AB ON a AB =⋅=,所以12||||S BD S AB =. 在C 1和C 2的方程中分别令0x =,可得A y m =,B y n =,D y m =-, 于是||||1||||1B D A B y y BD m n AB y y m n λλ-++===---. 第20题解若12S S λ=,则11λλλ+=-,化简得2210λλ--=. 由1λ>,可解得1λ=. 故当直线l 与y 轴重合时,若12S S λ=,则1λ. 解法2:如图1,若直线l 与y 轴重合,则||||||BD OB OD m n =+=+,||||||AB OA OB m n =-=-;111||||||22S BD OM a BD =⋅=,211||||||22S AB ON a AB =⋅=.所以12||1||1S BD m n S AB m n λλ++===--. 若12S S λ=,则11λλλ+=-,化简得2210λλ--=. 由1λ>,可解得1λ=. 故当直线l 与y 轴重合时,若12S S λ=,则1λ.(Ⅱ)解法1:如图2,若存在与坐标轴不重合的直线l ,使得12S S λ=. 根据对称性, 不妨设直线l :(0)y kx k =>,点(,0)M a -,(,0)N a 到直线l 的距离分别为1d ,2d ,则因为1d ==,2d ==12d d =.又111||2S BD d =,221||2S AB d =,所以12||||S BD S AB λ==,即||||BD AB λ=. 由对称性可知||||AB CD =,所以||||||(1)||BC BD AB AB λ=-=-, ||||||(1)||AD BD AB AB λ=+=+,于是||1||1AD BC λλ+=-. ① 将l 的方程分别与C 1,C 2的方程联立,可求得A x =B x =.根据对称性可知C B x x =-,D A x x =-,于是2||||2A B x AD BC x == ② 从而由①和②式可得第21题解答图1第21题解答图2令1(1)t λλλ+=-,则由m n >,可得1t ≠,于是由③可解得222222(1)(1)n t k a tλ-=-.因为0k ≠,所以2k >. 于是③式关于k 有解,当且仅当22222(1)0(1)n t a t λ->-, 等价于2221(1)()0t t λ--<. 由1λ>,可解得11t λ<<,即111(1)λλλλ+<<-,由1λ>,解得1λ>,所以当11λ<≤+l ,使得12S S λ=; 当1λ>l 使得12S S λ=.解法2:如图2,若存在与坐标轴不重合的直线l ,使得12S S λ=. 根据对称性, 不妨设直线l :(0)y kx k =>,点(,0)M a -,(,0)N a 到直线l 的距离分别为1d ,2d ,则 因为1d==,2d ==12d d =.又111||2S BD d =,221||2S AB d =,所以12||||S BD S AB λ==. 因为||||A B A Bx x BD AB x x λ+==-,所以11A B x x λλ+=-. 由点(,)A A A x kx ,(,)B B B x kx 分别在C 1,C 2上,可得222221A A x k x a m +=,222221B B x k x a n +=,两式相减可得22222222()0A B A B x x k x x a m λ--+=, 依题意0A B x x >>,所以22AB x x >.所以由上式解得22222222()()A B B A m x x k a x x λ-=-. 因为20k >,所以由2222222()0()A B B A m x x a x x λ->-,可解得1A B x x λ<<. 从而111λλλ+<<-,解得1λ> 当11λ<≤+l ,使得12S S λ=; 当1λ>l 使得12S S λ=.22. (Ⅰ)因为()(1)(1)(1)(1)[(1)1]r r f x r x r r x '=++-+=++-,令()0f x '=,解得0x =.当10x -<<时,()0f x '<,所以()f x 在(1,0)-内是减函数; 当0x >时,()0f x '>,所以()f x 在(0,)+∞内是增函数.故函数()f x 在0x =处取得最小值(0)0f =. (Ⅱ)由(Ⅰ),当(1,)x ∈-+∞时,有()(0)0f x f ≥=,即世纪金榜 圆您梦想 第11页(共11页) 山东世纪金榜科教文化股份有限公司 1(1)1(1)r x r x ++≥++,且等号当且仅当0x =时成立,故当1x >-且0x ≠时,有1(1)1(1)r x r x ++>++. ① 在①中,令1x n =(这时1x >-且0x ≠),得111(1)1r r n n+++>+. 上式两边同乘1r n +,得11(1)(1)r r r n n n r +++>++,即11(1).1r r rn n n r +++-<+ ② 当1n >时,在①中令1x n =-(这时1x >-且0x ≠),类似可得 11(1).1r r rn n n r ++-->+ ③ 且当1n =时,③也成立. 综合②,③得1111(1)(1).11r r r r r n n n n n r r ++++--+-<<++ ④ (Ⅲ)在④中,令13r =,n 分别取值81,82,83,…,125,得44443333338180(8281)44--(),44443333338281(8382)44-<-(),44443333338382(8483)44-<<-(), ………4444333333125124(126125)44-<-(. 将以上各式相加,并整理得444433333312580(12681)44S -<<-(). 代入数据计算,可得4433312580210.24-≈(),4433312681210.94-≈(). 由S ⎡⎤⎢⎥的定义,得211S =⎡⎤⎢⎥.。
湖北文理专升本试题及答案
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2. 请在答题卡上用黑色签字笔填写姓名和考号。
3. 所有答案必须写在答题卡上,写在试卷上的答案无效。
一、选择题(每题2分,共20分)1. 下列哪个选项是湖北文理学院的简称?A. 湖文理B. 湖理工C. 湖文院D. 湖理院答案:A2. 湖北文理学院位于哪个城市?A. 武汉B. 襄阳C. 宜昌D. 荆州答案:B3. 专升本是指什么?A. 专科生升本科B. 本科生升硕士C. 硕士生升博士D. 中学生升专科答案:A4. 以下哪个不是专升本考试的科目?A. 语文B. 数学C. 英语D. 体育答案:D5. 专升本考试通常在每年的哪个月份进行?A. 1月B. 3月C. 6月D. 9月答案:C(此处省略其他选择题,共10题)二、填空题(每空1分,共10分)1. 湖北文理学院的校训是“厚德、______、求实、创新”。
答案:博学2. 专升本考试通常由______组织。
答案:各省教育考试院3. 专升本考试的报名条件之一是必须具有______学历。
答案:全日制专科(此处省略其他填空题,共5空)三、简答题(每题10分,共20分)1. 请简述专升本考试的目的。
答案:专升本考试的目的在于为专科生提供一个继续深造的机会,通过考试选拔优秀专科生进入本科阶段学习,以提高个人学历和专业素养。
2. 专升本考试通常包含哪些科目?答案:专升本考试通常包含语文、数学、英语等基础科目,以及根据专业不同设置的专业科目。
四、论述题(每题15分,共30分)1. 论述专升本考试对于个人发展的意义。
答案:专升本考试对于个人发展具有重要意义。
首先,它为专科生提供了一个提升学历的平台,有助于个人职业发展和晋升。
其次,通过专升本考试进入本科学习,可以拓宽知识面,增强专业能力。
最后,专升本考试也是对个人学习能力和自我管理能力的一次考验,有助于培养终身学习的习惯。
2. 论述湖北文理学院专升本考试的报名流程。
2013年专转本高等数学试卷及答案解析
A.任意实数
B. ln 2
C. 2
D. 0
二、填空题(本大题共 6 小题,每小题 4 分,满分 24 分)
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.
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旋转体体积V2 ;
(2)问当 a 为何值时,V1 +V2 取得最大值?试求此最大值.
22.设函数 f (x) 在 (0, +∞) 内连续, f (1) = 5 ,且对所有 x,t ∈ (0, +∞) ,满足
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20.求非齐次微分方程 y′′ − 3y′ + 2 y = xex 的通解.
四、综合题(本大题共 2 小题,每小题 10 分,满分 20 分)
21.设函数 f (x) = 2x3 − 3x2 −12x +13 ,试求:
(1)函数 f (x) 的单调区间与极值;
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.
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2013年湖北文理学院专升本(高等数学)真题试卷(题后含答案及解析)
2013年湖北文理学院专升本(高等数学)真题试卷(题后含答案及解析)题型有:1. 选择题 2. 填空题 3. 解答题 4. 证明题一、选择题在每小题给出的四个选项中,只有一项是符合要求的。
1.设a是一个常数,且f(x)=a,则函数f(x)在点x0处( ).A.可以有定义,也可无定义B.一定有定义C.一定无定义D.有定义,且f(x0)=a正确答案:A2.当x→0时,2sinxcosx与x比较是( )无穷小量.A.等价的B.同阶的C.较高阶的D.较低阶的正确答案:B3.下列函数中在区间[-2,2]上满足罗尔定理条件的是( ).A.y=1+|x|B.y=x2+1C.y=D.y=x3+1正确答案:B4.下列等式中成立的是( ).A.d∫f(x)dx=f(x)B.d∫f(x)dx=f(x)dxC.∫f(x)dx=f(x)+CD.∫f(x)dx=f(x)dx正确答案:B5.若y1,y2是某个二阶齐次线性方程的解,则C1y1+C2y2(C1、C2∈R)是方程的( ).A.通解B.特解C.解D.全部解正确答案:C二、填空题6.函数z=ln(x2+y2-2)+的定义域为_______.正确答案:((x,y)|2<x2+y2≤4}7.设函数f(x)=,如果f(x)在x=0处连续,则a=_______.正确答案:38.设函数y=xe-x,则曲线的拐点为_______.正确答案:(2,2e-2)9.改变二次积分的积分次序,∫01dx f(x,y)dy=_______.正确答案:∫01dy f(x,y)dx10.函数ln(1+x)展开成x的幂级数为_______.正确答案:三、解答题解答时应写出推理、演算步骤。
11.正确答案:12.正确答案:13.y=,求y’.正确答案:14.求由方程1-y+xey=0所确定的隐函数的导数.正确答案:方程两边对x求导,其中y为x的函数,得-y’+ey+xey.y’=0,于是15.设z=u2+v2,u=x+y,v=x-y,求正确答案:由题可得,=2u.1+2v.1=2(x+y)+2(x-y)=4x,=2u.1+2v.(-1)=2(x+y)-2(x-y)=4y.16.y=,求dy.正确答案:∵y=[ln(x-6)-ln(x+6)],17.z=arcsin,求dz.正确答案:18.正确答案:19.dxdy,其中D是由直线y=2x,y=x,x=4,x=2所围成的区域.正确答案:积分区域D如图所示,易知区域D可表示为则20.计算∫L(x2+y2)dx+(x2-y2)dy,L为y=1-|1-x|(0≤x≤2)依x增加的方向.正确答案:由题,L可分为两段,故原积分=∫L1(x2+y2)dx+(x2-y2)dy=∫L2(x2+y2)dx+(x2-y2)dy=∫012x2dx+∫12[x2+(2-x)2+(2-x)2-x2]dx21.计算∫Lex[(1-cosy)dx-(y-siny)dy],其中L是y=sinx从O(0,0)到B(π,0)的一段弧,要求利用格林公式.正确答案:首先计算积分∫L’ex[(1-cosy)dx-(y-siny)dy],其L’为从B(π,0)到O(0,0)的直线段,而∫L’,ex[(1-cosy)dx-(y-siny)dy]=0,设D为如图所示的区域,由格林公式,得-∫L+L’ex[(1-cosy)dx-(y-siny)dy]22.判别级数的敛散性.正确答案:∵∴原级数收敛.23.求级数(x-1)n的收敛域.正确答案:∵∴原级数收敛半径为19/25,令|x-1|<6/25,得19/25<x<31/25,且当x=19≥25时,原级数为(-1)n.n发散,∴原级数的收敛域为(19/25,31/25).24.求微分方程y”-5y’+6y=xe2x的通解.正确答案:原方程对应的齐次方程的特征方程为r2-5r+6=0,得特征根为r1=2,r2=3,故齐次方程的通解为y=C1e2x+C2e3x,由于r1=2为单特征根,由题可设原微分方程的通解为y=x(Ax+B)e2x,代入原方程,对比x的系数,可得A=-,B=-1,故原微分方程通解为y=C1e2x+C2e3x-e2x(x2+2x).25.求表面积为a2而体积为最大的长方体的体积.正确答案:设长方体的长宽高分别为x,y,z,则其表面积为2(xy+xz+yz)=a2①,而所求体积V=xyz②,题中即为求体积V在条件①下的最值,构造拉格朗日函数,L=xyz-λ(2xy+2xz+2yz-a2),由于实际问题,最大值一定存在,故当长方体为棱长为a的正方体时,其体积最大,最大体积Vmax=a3.证明题26.证明不等式:ex>x+1(x≠0).正确答案:构造函数f(x)=ex-x-1,f’(x)=ex-1,令f’(x)=0,得x=0,且当x <0时,f’(x)<0,当(x)>0时,f’(x)>0,x=0是f(x)在(-∞,+∞)上唯一极小值点,故为最小值点,故f(x)≥f(0)=0在R上成立,且等号只在x=0取得,故ex >x+1,在x≠0时成立.。
湖北文理学院专升本高等数学大纲及试卷(中信鸿图教育)
《高等数学》考试大纲一、基本要求:考生应按本大纲的要求,了解或理解“高等数学”中函数、极限和连续、一元函数微分学、一元函数积分学、向量代数与空间解析几何、多元函数微积分学、无穷级数、常微分方程的基本概念与基本理论;学会、掌握或熟练掌握上述各部分的基本方法。
应注意各部分知识的结构及知识的内在联系;应具有一定的抽象思维能力、逻辑推理能力、运算能力、空间想象能力;有运用基本概念、基本理论和基本方法正确地推理证明,准确地计算;能综合运用所学知识分析并解决简单的实际问题。
本大纲对内容的要求由低到高,对概念和理论分为“了解”和“理解”两个层次;对方法和运算分为“会”、“掌握”和“熟练掌握”三个层次。
二、考试方法和时间:考试方法为闭卷考试,考试时间为90分钟。
三、考试题型大致比例:选择题:100%,试卷满分:100分。
四、考试内容和要求:第一章函数、极限和连续(一)函数考试内容:(1)函数的概念:函数的定义函数的表示法分段函数;(2)函数的简单性质:单调性奇偶性有界性周期性;(3)反函数:反函数的定义反函数的图象;(4)函数的四则运算与复合运算;(5)基本初等函数:幂函数指数函数对数函数三角函数反三角函数;(6)初等函数。
考试要求:(1)理解函数的概念,会求函数的定义域、表达式及函数值;会求分段函数的定义域、函数值,并会做出简单的分段函数图象;(2)理解和掌握函数的单调性、奇偶性、有界性和周期性,会判断所给函数的类别;(3)了解函数y=ƒ(x)与其反函数y=ƒ-1(x)之间的关系(定义域、值域、图象),会求单调函数的反函数;(4)理解和掌握函数的四则运算与复合运算,熟练掌握复合函数的复合过程;(5)掌握基本初等函数的简单性质及其图像象;(6)了解初等函数的概念;(7)会建立简单实际问题的函数关系式。
(二)极限考试内容:(1)数列极限的概念:数列 数列极限的定义;(2)数列极限的性质:唯一性 有界性 四则运算定理 夹逼定理 单调有界数列 极限存在定理;(3)函数极限的概念:函数在一点处极限的定义 左、右极限及其与极限的关系x 趋于无穷(x →∞,x →+∞,x →-∞)时函数的极限 函数极限的几何意义;(4)函数极限的定理:唯一性定理 夹逼定理 四则运算定理;(5)无穷小量和无穷大量:无穷小量与无穷大量的定义 无穷小量与无穷大量的关系 无穷小量与无穷大量的性质 两个无穷小量阶的比较;(6)两个重要极限 1sin lim0=→x x x e xx x =+∞→)11(lim 基本要求:(1)理解极限的概念(对极限定义中“ε- N ”、“ε- δ”、“ε- M ”的描述不作要求),能根据极限概念分析函数的变化趋势。
湖北文理学院2011-2012年度《高等数学》期末考试试卷
襄樊学院2011-2012学年度上学期《高等数学》试卷(A )院别 专业及班级 学号 姓名课程类别:必修 适用专业:一、选择题(从以下各题给出的四个备选答案中,选出一个正确答案,并将题号写在题干后面的括号内.每小题2分,共20分)1、11lim(sin sin )n n n n n→∞-=( )A -1B 0C 1D ∞2、当0x →时,下列变量与x 相比为等价无穷小量的是( ) A 2sin x x - B sin x x -C 2sin x x - D 1cos x -3、设10()00x f x xx ≠=⎨⎪=⎩,则0x =是函数()f x 的( ). A 可去间断点 B 无穷间断点 C 连续点 D 跳跃间断点4、.设函数f(x )在点0x 处可导,则000(2)()limx f x x f x x→-- =( )A02()f x ' B 01()2f x ' C 01()2f x '- D02()f x '-5、设函数1()1xf x x-=+,则(0)f '=( )A -2B -1C 1D 26、曲线3y x =在点(1,1)处的切线斜率为( ) A 0 B 1 C 2D 37、函数23()(32)1f x x =---的极小值点为( )A 1x =B 0x =C 23x = D 不存在 8、函数()lnsin f x x =在5[,]66ππ上满足罗尔定理的ξ= ( )A2πB 1C πD 3 9、若12()sin xF x t dt =⎰,则()F x '=()A 2sin x - B 2sin x C 22cos x x D 22cos x x - 10、下列无穷限反常积分发散的是( ) Ae d x x-+⎰1∞Bd x +⎰1e x ∞C211d x x +⎰∞D21d 1x x++⎰1∞二、填空题(每小题3分,共18分)1、数列极限12lim 21n n n +→∞+=____________.2、曲线3y x =的拐点是 . 3、若函数f (x )=在x =0点连续,则b =____________.4、已知()f x x '=,则微分()x df e = . 5. 微分方程定积分30y y y '''+=的阶数为____________. 6. 定积分222||2x x dx x -++⎰=____________.三、计算题(要求写出主要计算步骤及结果,共46分)1.设函数tan 23xy =,求d d y x .(5分) 2、求极限00ln(12)d lim 1cos xx t t x→+-⎰. (5分)3、设1(cot )xy x =,求y '. (5分) 4、设221t x y t⎧=⎪⎨⎪=-⎩,求22d y dx . (5分)5、求积分22arctan d 1x x x x ++⎰.(5分) 6、求积分4tan sec x xdx ⎰. (5分)7、计算定积分40I x =⎰.(8分) 8、求微分方程244(21)xy y y x e '''-+=+的通解.(8分)四、应用题(11分)设D 是由曲线ln y x =,直线y e =及y 轴围成的平面区域. (1)求D 的面积S .(2)求D 绕y 轴一周的旋转体体积y V .五、证明题(5分)证明方程3310x x -+=在区间(0,1)内有且只有一个根。
2013年普通高等学校招生全国统一考试(湖北卷)数学试题 (理科) word解析版
2013年普通高等学校招生全国统一考试(湖北卷)数 学(理工类)解析版一、选择题 1、在复平面内,复数21iz i=+(i 为虚数单位)的共轭复数对应的点位于( ) A. 第一象限 B. 第二象限 C. 第三象限 D. 第四象限【解析与答案】211iz i i==++,1z i ∴=-。
故选D 【相关知识点】复数的运算2.已知全集为R ,集合1{()1}2x A x =≤,2{680}B x x x =-+≤,则R A C B =( )A .{0}x x ≤B .{24}x x ≤≤C .{024}x x x ≤<>或D .{024}x x x <≤≥或 【解析与答案】[)0,A =+∞,[]2,4B =,[)()0,24,R AC B ∴=+∞。
故选C【相关知识点】不等式的求解,集合的运算3、在一次跳伞训练中,甲、乙两位学员各跳一次,设命题p 是“甲降落在指定范围”,q 是“乙降落在指定范围”,则命题“至少有一位学员没有降落在指定范围”可表示为( ) A.()()p q ⌝∨⌝ B. ()p q ∨⌝ C. ()()p q ⌝∧⌝ D.p q ∨【解析与答案】“至少有一位学员没有降落在指定范围”即:“甲或乙没有降落在指定范围内”。
故选A 。
【相关知识点】命题及逻辑连接词4、将函数()sin y x x x R =+∈的图像向左平移()0m m >个长度单位后,所得到的图像关于y 轴对称,则m 的最小值是( )A. 12πB. 6πC. 3πD. 56π 【解析与答案】2cos 6y x π⎛⎫=- ⎪⎝⎭的图像向左平移()0m m >个长度单位后变成2cos 6y x m π⎛⎫=-+ ⎪⎝⎭,所以m 的最小值是6π。
故选B 。
【相关知识点】三角函数图象及其变换5、已知04πθ<<,则双曲线22122:1cos sin x y C θθ-=与222222:1sin sin tan y x C θθθ-=的( )A.实轴长相等B.虚轴长相等C.焦距相等D. 离心率相等 【解析与答案】双曲线1C 的离心率是11cos e θ=,双曲线2C 的离心率是21cos e θ==,故选D 【相关知识点】双曲线的离心率,三角恒等变形6、已知点()1,1A -、()1,2B 、()2,1C --、()3,4D ,则向量AB 在CD 方向上的投影为( )A.C.D. 【解析与答案】()2,1AB =,()5,5CD =,5AB CD CD∴==,故选A 。
2013年湖北文理学院专升本《化工原理》试题
湖北文理学院2013年“专升本”考试《化工原理》试题成绩一、填空(每空1分,共20分)1.雷诺准数Re是用来判断__ ,若为____ ,则Re<2000;若为______ ,则Re>4000;若为____ ,则2000<Re<4000。
2.离心泵的性能参数有、、、。
3.精馏设计中,当回流比减小时所需理论板数。
4.写出三种测量流量的仪表、、。
5.分离任务要求一定,当回流比一定时,在五种进料状况中,进料的q值为零。
6.离心泵启动前应以保护电机,往复泵调节流量最常用的方法是。
7.热量传递的方式有、、。
8. 干燥介质经过预热器的目的是。
9.重力场中,利用分散相和连续相之间的不同使之发生相对运动而分离的过程,称为重力沉降。
二、选择题(每题有四个备选项,从中选出一个正确答案。
每小题2分,共20分)1.空气的干球温度为t,湿球温度为t w,露点为t d,当空气的相对湿度为80%,则( ) 。
A. t= t w=t dB. t<t w<t dC. t>t w>t dD. t>t w=t d2.一套管换热器,环隙为120℃蒸汽冷凝,管内空气从20℃被加热到50℃,则管壁温度应接近于()。
A. 35℃B. 77.5℃C. 120℃D. 50℃3.混合液两组分的相对挥发度愈小,则表明用蒸馏方法分离该混合液愈()A.容易B.困难C.完全D.不完全4. 对流干燥操作进行的必要条件是()。
A.湿物料的温度>空气的温度B.湿物料表面的水汽压力<空气的水汽压力C.湿物料的温度<空气的温度D.湿物料表面的水汽压力>空气的水汽压力5.离心泵铭牌上标明的流量是指( )。
A. 效率最高时的流量B. 泵的最大流量C. 扬程最大时的流量D. 最小扬程时的流量6.对于气膜控制的吸收过程,为了提高吸收速率,应着力改善( )。
A.气膜侧的传质条件B.液膜侧的传质条件C.两侧同时改善D.无法判断7.下列说法不正确的有()。
A. 凡理想溶液,在压强不高和温度不变条件下,亨利定律和拉乌尔定律一致B. 难溶气体的亨利系数大,易溶气体的亨利系数小C. 难溶气体的相平衡常数大,而其溶解度系数小D. 温度升高亨利系数变小,而其溶解度系数增大8.真空表读数表示被测流体的绝对压强大气压强的读数。
