河南省洛阳市第一高级中学高二下学期周练(3.15)数学(文)试题Word版含答案

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河南省洛阳市第一高级中学2019_2020学年高二数学下学期周练试题(3.15)文

河南省洛阳市第一高级中学2019_2020学年高二数学下学期周练试题(3.15)文

河南省洛阳市第一高级中学2019-2020学年高二数学下学期周练试题(3.15)文1.若直线l 经过点A(1,2),且在x 轴上的截距的取值范围是(-3,3),则其斜率的取值范围是( )A .-1<k<15B .k>1或k<12 C.15<k<1D .k>12或k<-12.已知直线y =kx +1与曲线y =x 3+ax +b 切于点(1,3),则b 的值为( ) A .3 B .-3 C .5 D .-53.“m =-1”是“直线mx +(2m -1)y +2=0与直线3x +my +3=0垂直”的( ) A .充分而不必要条件 B .必要而不充分条件 C .充要条件D .既不充分也不必要条件4.直线y =2x +1关于点(1,1)对称的直线方程是( ) A .y =2x -1 B .y =-2x +1 C .y =-2x +3D .y =2x -35.圆x 2+y 2+2x +4y -3=0上到直线x +y +1=0的距离为2的点共有( ) A .1个 B .2个 C .3个 D .4个 6.若直线x -y +2=0与圆C :(x -3)2+(y -3)2=4相交于A ,B 两点,则CA →·CB →的值为( ) A .-1 B .0 C .1D .67.已知圆C :(x -3)2+(y -4)2=1和两点A(-m ,0),B(m ,0)(m>0),若C 上存在的点P ,使得∠APB=90°,则m 的最大值为( )A .7B .6C .5D .48.如图,在正方体ABCD -A 1B 1C 1D 1中,P 是侧面BB 1C 1C 内一动点.若P 到直线BC 与直线C 1D 1的距离相等,则动点P 的轨迹所在的曲线是( )A .线段B .圆C .双曲线一部分D .抛物线的一部分9.已知椭圆C 1:x 2a 2+y 2b 2=1(a>b>0)与圆C 2:x 2+y 2=b 2,若在椭圆C 1上存在点P ,使得由点P所作的圆C 2的两条切线互相垂直,则椭圆C 1的离心率的取值范围是( ) A .[12,1) B .[22,32] C .[22,1)D .[32,1) 10.已知点P 为双曲线x 216-y29=1右支上一点,点F 1,F 2分别为双曲线的左、右焦点,M 为△PF 1F 2的内心,若S △PMF 1=S △PMF 2+8,则△MF 1F 2的面积为( ) A .27 B .10 C .8D .611.若圆C :x 2+y 2+2x -4y +3=0关于直线2ax +by +6=0对称,则由点(a ,b)向圆所作的切线长的最小值为________.12.直线l 1和l 2是圆x 2+y 2=2的两条切线.若l 1与l 2的交点为(1,3),则l 1与l 2的夹角的正切值等于________.13.椭圆x 2a 2+y 2b 2=1(a>b>0)的右焦点F(c ,0)关于直线y =bc x 的对称点Q 在椭圆上,则椭圆的离心率是________.14.平面直角坐标系xOy 中,双曲线C 1:x 2a 2-y 2b 2=1(a>0,b>0)的渐近线与抛物线C 2:x 2=2py(p>0)交于O ,A ,B 三点,若△OAB 的垂心为C 2的焦点,则C 1的离心率为________.15.已知实数x ,y 满足x 2+y 2-2y =0.(1)求2x +y 的取值范围;(2)若x +y +c≥0恒成立,求实数c 的取值范围.16.在直角坐标系xOy 中,以M(-1,0)为圆心的圆与直线x -3y -3=0相切. (1)求圆M 的方程;(2)已知A(-2,0),B(2,0),圆内的动点P 满足|PA|·|PB|=|PO|2,求PA →·PB →的取值范围.17.如图所示,双曲线的中心在坐标原点,焦点在x 轴上,F 1,F 2分别为左、右焦点,双曲线的左支上有一点P ,∠F 1PF 2=π3,且△PF 1F 2的面积为23,又双曲线的离心率为2,求该双曲线的方程.3月15日文科数学周测答案1.D 2.A 3. A 4.D 5.C 6. B 7.B 8.D 9. C 10. B 11.4 12. 4313.2214.3215.已知实数x ,y 满足x 2+y 2-2y =0. (1)求2x +y 的取值范围;(2)若x +y +c≥0恒成立,求实数c 的取值范围.解 (1)方法一:圆x 2+(y -1)2=1的参数方程为 ⎩⎪⎨⎪⎧x =cos θ,y =1+sin θ,--------2分∴2x +y =2cos θ+sin θ+1.------------------------------------------------------------3分 ∵-5≤2cos θ+sin θ≤5,--------------------------------------4分 ∴1-5≤2x+y≤5+1.----------------------------------------------------------------5分方法二:2x +y 可看作直线y =-2x +b 在y 轴的截距,当直线与圆相切时b 取最值,此时|2×0+1-b|5=1.-----------------------------------------------------------------------------3分 ∴b=1±5,∴1-5≤2x+y≤1+5.-------------------------------------------------5分(2)∵x+y =cos θ+1+sin θ=2sin (θ+π4)+1,------------------------7分∴x+y+c的最小值为1-2+c.---------------------------------------------------------8分 ∴x+y+c≥0恒成立等价于1-2+c≥0.---------------------------------------------9分 ∴c的取值范围为c≥2-1.---------------------------------------------------------------10分16.在直角坐标系xOy 中,以M(-1,0)为圆心的圆与直线x -3y -3=0相切. (1)求圆M 的方程;(2)已知A(-2,0),B(2,0),圆内的动点P 满足|PA|·|PB|=|PO|2,求PA →·PB →的取值范围.解 (1)依题意,圆M 的半径r 等于圆心M(-1,0)到直线x -3y -3=0的距离,即r =|-1-3|1+3=2.---------------------------------------------------------------------------------------3分 ∴圆M的方程为(x+1)2+y2=4.-------------------------------------------------------------4分 (2)设P(x ,y),由|PA||PB|=|PO|2,得 (x +2)2+y 2·(x -2)2+y 2=x 2+y 2, 即x2-y2=2.---------------------------------------------------------------------------------------6分∴PA →·PB →=(-2-x ,-y)·(2-x ,-y) =x2-4+y2=2(y2-1).-------------------------------------------------------------------------8分∵点P 在圆M 内,∴(x +1)2+y 2<4,∴0≤y 2<4,∴-1≤y 2-1<3. ∴PA→·PB→的取值范围为[-2,6).------------------------------------------------------------10分17.如图所示,双曲线的中心在坐标原点,焦点在x 轴上,F 1,F 2分别为左、右焦点,双曲线的左支上有一点P ,∠F 1PF 2=π3,且△PF 1F 2的面积为23,又双曲线的离心率为2,求该双曲线的方程.解 设双曲线的方程为x 2a 2-y2b 2=1,----------------------------------------1分∴F 1(-c ,0),F 2(c ,0),P(x 0,y 0). 在△PF 1F 2中,由余弦定理,得|F 1F 2|2=|PF 1|2+|PF 2|2-2|PF 1|·|PF 2|·cosπ3-----------------------------------------------------3分 =(|PF 1|-|PF 2|)2+|PF 1|·|PF 2|. 即4c2=4a2+|PF 1|·|PF 2|.----------------------------------------------------------------------------5分 又∵S△PF 1F 2=23,∴12|PF 1|·|PF 2|·sin π3=23.------------------------------------------------------------------------7分∴|PF 1|·|PF 2|=8. ∴4c2=4a2+8,即b2=2.-----------------------------------------------------------------------------8分又∵e=c a =2,∴a 2=23.∴所求双曲线方程为3x22-y 22=1.-------------------------------------------------------------------10分。

河南省高二下学期第一次月考数学试卷(文科)

河南省高二下学期第一次月考数学试卷(文科)

河南省高二下学期第一次月考数学试卷(文科)姓名:________ 班级:________ 成绩:________一、单选题 (共12题;共24分)1. (2分)设斜率为2的直线过抛物线的焦点F,且和轴交于点A,若△OAF(O为坐标原点)的面积为4,则抛物线方程为().A .B .C .D .2. (2分)观察图形规律,在其右下角的空格内画上合适的图形为()A .B .C .D .3. (2分) (2017高二下·安阳期中) 复数z1=1+bi,z2=﹣2+i,若的实部和虚部互为相反数,则实数b 的值为()A . 3B .C . ﹣D . ﹣34. (2分)已知U=R,函数y=ln(1﹣x)的定义域为M,集合N={x|x2﹣x<0}.则下列结论正确的是()A . M∩N=NB . M∩(∁UN)=∅C . M∪N=UD . M⊆(∁UN)5. (2分)若直线y=kx+4+2k与曲线y=有两个交点,则k的取值范围是()A . [1,+∞)B . [﹣1,﹣)C . (, 1]D . (﹣∞,﹣1]6. (2分) (2016高二下·黑龙江开学考) 执行如图所示的程序框图,若输入n的值为6,则输出s的值为()A . 105B . 16C . 15D . 17. (2分) (2020高一上·安庆期末) 若函数的图像经过点 ,则其图像必经过点()A .B .C .D .8. (2分)(2016·安徽模拟) 若将函数f(x)=cosx(sinx+cosx)﹣的图象向右平移φ个单位,所得函数是奇函数,则φ的最小正值是()A .B .C .D .9. (2分)等差数列中,,,设是数列的前n项和,则S8=()A . -16B . 16C . -32D . 3210. (2分) (2016高一上·天水期中) 若log2a<0,()b>1,则()A . a>1,b>0B . a>1,b<0C . 0<a<1,b>0D . 0<a<1,b<011. (2分)已知向量,,则“”是“”的()A . 充分不必要条件B . 必要不充分条件C . 充要条件D . 既不充分也不必要条件12. (2分)若复数z满足,则等于()A .B .C .D .二、填空题 (共4题;共4分)13. (1分) (2016高三上·黑龙江期中) 设△ABC中,角A,B,C的对边分别为a、b、c,且2sinA=sinB+sinC,a=2,则△ABC面积的最大值为________.14. (1分) (2016高一下·信阳期末) 某同学在求解某回归方程中,已知x,y的取值结果(y与x呈线性相关)如表:x234y64m并且求得了线性回归方程为 =﹣ x+ ,则m等于________.15. (1分) (2017高一下·珠海期末) 已知,则△ABM 与△ACM 的面积的比值为________.16. (1分) (2017高二下·太和期中) 已知F是椭圆C: + =1的右焦点,P是C上一点,A(﹣2,1),当△APF周长最小时,其面积为________.三、解答题 (共5题;共40分)17. (5分) (2018高二下·聊城期中) 设复数的共轭复数为,且,,复数对应复平面的向量,求的值和的取值范围.18. (10分) (2017高二上·河南月考) 已知抛物线关于轴对称,它的顶点在坐标原点,点在抛物线上.(1)写出该抛物线的标准方程及其准线方程;(2)过点作两条倾斜角互补的直线与抛物线分别交于不同的两点 ,求证:直线的斜率是一个定值.19. (5分)(2017·石家庄模拟) 已知抛物线C:y2=2px(p>0)过点M(m,2),其焦点为F,且|MF|=2.(Ⅰ)求抛物线C的方程;(Ⅱ)设E为y轴上异于原点的任意一点,过点E作不经过原点的两条直线分别与抛物线C和圆F:(x﹣1)2+y2=1相切,切点分别为A,B,求证:直线AB过定点F(1,0).20. (10分) (2015高三上·辽宁期中) 数列{an}满足a1=1,nan+1=(n+1)an+n(n+1),n∈N* .(1)证明:数列{ }是等差数列;(2)设bn=3n• ,求数列{bn}的前n项和Sn .21. (10分) (2016高一上·沽源期中) 如图1:已知正方形ABCD的边长是2,有一动点M从点B出发沿正方形的边运动,路线是B→C→D→A.设点M经过的路程为x,△ABM的面积为S.(1)求函数S=f(x)的解析式及其定义域;(2)在图2中画出函数S=f(x)的图象.参考答案一、单选题 (共12题;共24分)答案:1-1、考点:解析:答案:2-1、考点:解析:答案:3-1、考点:解析:答案:4-1、考点:解析:答案:5-1、考点:解析:答案:6-1、考点:解析:答案:7-1、考点:解析:答案:8-1、考点:解析:答案:9-1、考点:解析:答案:10-1、考点:解析:答案:11-1、考点:解析:答案:12-1、考点:解析:二、填空题 (共4题;共4分)答案:13-1、考点:解析:答案:14-1、考点:解析:答案:15-1、考点:解析:答案:16-1、考点:解析:三、解答题 (共5题;共40分)答案:17-1、考点:解析:答案:18-1、答案:18-2、考点:解析:考点:解析:答案:20-1、答案:20-2、考点:解析:答案:21-1、答案:21-2、考点:解析:。

河南省洛阳市第一高级中学高二数学下学期6月“周练”试卷 理.doc

河南省洛阳市第一高级中学高二数学下学期6月“周练”试卷 理.doc

河南省洛阳市第一高级中学高二数学下学期6月“周练”试卷 理一、选择题1、在平面直角坐标系中,经伸缩变换后曲线方程x 2+ y 2= 4,变换为椭圆方程214y x ''+=,此伸缩变换公式是( )A 、12x x y y ⎧'=⎪⎨⎪'=⎩B 、2x x y y '=⎧⎨'=⎩C 、4x x y y '=⎧⎨'=⎩D 、24x x y y '=⎧⎨'=⎩2、已知曲线C 1、C 2的极坐标方程分别为cos 3ρϕ=,4cos (0, 0)2πρϕρϕ=≥≤≤,则曲线C 1与C 2的交点的极坐标为( ) A、)6πB、, )23πC、)3πD、()26π 3、极坐标方程2cos 0()R θρ=∈表示图形是( ) A 、两条射线B 、两条相交直线C 、一条直线D 、一条直线和一条射线4、已知P 点极坐标为(4, π),则过点P 且垂直于极轴的直线的极坐标方程为( ) A 、4ρ=B 、4cos ρθ=C 、4cos ρθ-=D 、4cos ρθ=5、已知抛物线C 1:y = 2x 2与抛物线C 2关于直线y = x 对称,则C 2的准线方程为( ) A 、18x =-B 、12x =C 、18x =D 、12x =-6、设双曲线22221(0, 0)x y a b a b-=>>的实轴长、虚轴长、焦距成等比数列,则双曲线离心率为( ) A、2B、12CD7、设M 为双曲线221916x y -=上位于第四象限内一点,12,F F 为两焦点且12:1:3MF M F =,则△MF 1F 2周长为( )A 、16B 、22C 、26D 、308、F 1、F 2分别为双曲线22221(0, 0)x y a b a b-=>>的左右焦点,A 、B 是以O 为圆心、以OF 1为半径的圆与双曲线左支两交点,且△F 2AB 为等边三角形,则双曲线离心率为( )ABCD 、19、函数y = lnx – x 在(0, ]e 上最大值为( )A 、eB 、1C 、-1D 、-e10、已知长方体ABCD -A 1B 1C 1D 1中,底面是连长为2的正方形,高为4,则点A 1到截面AB 1D 1的距离是( ) A 、83B 、38C 、43D 、34二、填空题1.已知圆的极坐标方程为()5sin 3cos 22=++θθρρ则此圆在直线0=θ上截得的弦长为2.正四棱锥底面边长为2,高为2。

河南省洛阳第一高级中学高二下学期第一次月考试题 数学(文) Word版含答案.pdf

河南省洛阳第一高级中学高二下学期第一次月考试题 数学(文) Word版含答案.pdf

命题人: 满分分时间分钟 “为纯虚数”是“=0”的( )。

A、充分不必要条件B、必要不充分条件C、充要条件D、既不充分,也不必要条件 2.设复数Z满足Zi=2-i,则|Z|=A. B. C. D.3 3.阅读右边的程序框图,运行相应的程序,则输出s的值为: A.-1 B.0 C.1 D.3 4.已知数列{an}的前n项和为Sn,且Sn=2an-2(n∈N*),则a2等于 A.4 B.2 C.1 D.-2 5.设则( ) A.都不大于 B.都不小于 C.至少有一个不大于 D.至少有一个不小于 6.利用独立性检验来考虑两个分类变量X和Y是否有关系时,通过查阅下表来确定断言“X和Y有关系”的可信度。

如果k>5.024,那么就有把握认为“X和Y有关系”的百分比为( ) P(k2>k)0.250.150.100.050.0250.0100.0050.001 k1.3232.0722.7063.845.0246.6357.87910.83A 25%B 75%C 2.5%D 97.5% 7.复数满足,则的最小值为( ) A、 B、 C、 D、 8.下列几个说法; ①由样本数据得到的线性回归方程=x+,则回归直线必过样本点的中心; ②将一组数据都加上同一个常数后,平均数等于原平均数加上这个常数,方差不变; ③在回归分析中当相关指数R2=1时,表明变量x,y是确定关系. 其中正确命题的个数是 A.3 8.2 C.1 D.0 9.已知△ABC中,AB=,BC=1,sinC=cosC,则△ABC的面积为 A. B. C. D. 10.直线y=-3x+m是曲线y=x3-3x2的一条切线,则实数m的值是 A.4 B.3 C.2 D.1 11.已知F1,F2分别是椭圆+=1(a>b>0)的左右两个焦点,过F1作x轴的垂线交椭圆于点P,若∠F1PF2=,则椭圆的离心率为 A. B. C. D. 12.若函数f(x)=xlnx-a有两个零点,则实数a的取值范围为 A.[0,] B.(-,) C.(0,] D.(-,0) 二、填空题:(每小题5分,共20分) 13.若x、y为共轭复数,且(x+y)2-3xyi=4-6i,则|x|+|y|=an}是等差数列,a1+ a3+ a5=105,a2+ a4+a6=99,Sn是{an}的前n项和,则使Sn达到最大值的n=. 15.若关于的不等式的解集为,则的取值范围是 . 16.若数列的通项公式,记, 试通过计算的值,推测出 三、解答题:(本大题共6小题.满分70分) 求证: 18.(12分) 在△ABC中,内角A,B,C的对边分别为a,b,c,且bsinA=acosB。

最新河南省洛阳市第一高级中学高二下学期周练(3.15)英语试题 Word版含答案

最新河南省洛阳市第一高级中学高二下学期周练(3.15)英语试题 Word版含答案

洛阳一高 2019-2020 学年第二学期英语周测试卷第一部分阅读理解(共两节,满分 40 分)第一节(共 15 小题;每小题 2 分,满分 30 分)阅读短文,从每题所给的选项中,选出最佳选项。

AThe things that kids choose to play with can impact our Earth. The manufacturingof toys and games can produce harmful pollution and non-biodegradable(不可生物降解的)waste, which is harmful for our planet. But some toymakers are creating items for kids that aim higher. They use natural or non-harmful materials, and find ways to reuse and recycle. Toys and kits (成套工具) can also teach kids about environmentally friendly solutions. Here are a few of our favorite low-impact,high-fun toys.Test the watersWater is Earth's most precious natural resource. Many people take it for granted,but not everybody in the world has access to clean water. Learn about the science behind one solution with Thames & Kosmos' Global Water Quality Experiment Kit. The kit comes with tools and instructions for conducting eight important experiments including testing the quality of water and making dirty water cleaner. ($15)Plant tomatoesWhen communities in dry, desert regions experience drought, it impacts their agricultural practices. Learn about water preservation and grow delicious cherry tomatoes with Back to the Roots' Self-Watering Tomato Planter. It features technology that African desert farmers have been using for thousands of years: a miniature clay pot releases water, but only when the surrounding soil has dried up. ($30)Draw with veggiesWee Can Too's Veggie Sidewalk Chalk is made from fruit and vegetable powders — it's practically safe to eat! The chalk, created using environmentally friendly ingredients, has none of the chemicals found in your typical sidewalk chalk. When the rain comes and washes away your masterpiece, no harmful pollutants will be entering the environment. ($12)Create with cardboardWhen cardboard breaks down in a landfill, it creates methane, a major greenhouse gas that contributes to global warming. Recycled cardboard can be transformed into a work of art with the Cardboard Tool Kit from UncommonGoods. The kit comes with 28 reusable parts for fastening cardboard pieces together. Now let your imagination go wild! ($13)1. What is special about Back to the Roots' small clay pot?A. It is very pretty.B. It is a recent invention.C. It can improve tomatoes' taste.D. It uses anti-drought technology.2. Which product needs users to be imaginative?A. Cardboard Tool Kit.B. Veggie Sidewalk Chalk.C. Self-Watering Tomato Planter.D. Global Water Quality Experiment Kit.3. What do the four products have in common?A. They are hard to use.B. They are Earth-friendly toys.C. They are good for kids' health.D. They are great choices for art-lovers.BSteven Stein likes to follow garbage trucks. His strange habit makes sense when you consider that he’s an environmental scientist who studies how to reduce litter, including things that fall off garbage trucks as they drive down the road. What is even more interesting is that one of Stein's jobs is defending an industry behind the plastic shopping bags.Americans use more than 100 billion thin plastic bags every year. So many end up in tree branches or along highways that a growing number of cities do not allow them at checkouts . The bags are prohibited in some 90 cities in California, including Los Angeles. Eyeing these headwinds, plastic-bag makers are hiring scientists like Stein to make the case that their products are not as bad for the planet as most people assume.Among the bag makers' argument: many cities with bans still allow shoppers to purchase paper bags, which are easily recycled but require more energy to produce and transport. And while plastic bags may be ugly to look at, they represent a small percentage of all garbage on the ground todayThe industry has also taken aim at the product that has appeared as its replacement: reusable shopping bags. The stronger a reusable bag is, the longer its life and the more plastic-bag use it cancels out. However, longer-lasting reusable bags often require more energy to make. One study found that a cotton bag must be used at least 131 times to be better for the planet than plastic.Environmentalists don't dispute (质疑)these points. They hope paper bags will be bannedsomeday too and want shoppers to use the same reusable bags for years.4. What has Steven Stein been hired to do?A. Help increase grocery sales.B. Recycle the waste material.C. Stop things falling off trucks.D. Argue for the use of plastic bags.5. What does the word “headwinds” in paragraph 2 refer to?A. Bans on plastic bags.B. Effects of city development.C. Headaches caused by garbage.D. Plastic bags hung in trees.6. What is a disadvantage of reusable bags according to plastic-bag makers?A. They are quite expensive.B. Replacing them can be difficult.C. They are less strong than plastic bags.D. Producing them requires more energy.7. What is the best title for the text?A. Plastic, Paper or NeitherB. Industry, Pollution and EnvironmentC. Recycle or Throw AwayD. Garbage Collection and Waste ControlCThere are two types of people in the world. Although they have equal degree of health and wealthand other comforts of life,one becomes happy and the other becomes unhappy. This arises from the different ways in which they consider things,persons,events and the resulting effects upon their minds.People who are to be happy fix their attention on the convenience of things:thepleasant partsof conversation ,the well prepared dishes ,the goodness of the wine and the fine weather. They enjoy all the cheerful things. Those who are to be unhappy think and speak only of the opposite things. Therefore , they are continually dissatisfied. By their remarks ,they sour the pleasure ofsociety, offend(hurt) many people, and make themselves disagreeable everywhere. If this turn ofmind was founded in nature,such unhappy persons would be the more to be pitied. The intention of criticizing and being disliked is perhaps taken up by imitation. It grows into a habit, unknown to its possessors. The habit may be strong, but it may be cured when those who have it realize its bad effects on their interests and tastes. I hope this little warning may be of service to them,and helpthem change this habit.Although in fact it is chiefly an act of the imagination,it has serious results inlife since it brings on deep sorrow and bad luck. Those people offend many others;nobody loves them,and no one treats them with more than the most common politeness and respect. This frequently puts them inbad temper and draws them into arguments. If they aim at getting some advantages insocial position or fortune,nobody wishes them success. Nor will anyone start a stepor speak a word to favor their hopes.If they bring on themselves public objections,no one will defend or excuse them,and many will join to criticize their wrongdoings. These should change this bad habit and be pleased with what is pleasing,without worrying needlessly about themselves and others.If they do not,it will be goodfor others to avoid any contact with them. Otherwise,it can be disagreeable and sometimes veryinconvenient,especially when one becomes mixed up in their quarrels.8. P eople who are unhappy .A. always consider things differently from othersB. usually are affected by the results of certain thingsC. usually misunderstand what others think or sayD. always discover the unpleasant side of certain things9. T he underlined phrase “sour the pleasure of society” in Paragraph 2 most nearly means “”.A. have a good taste with social lifeB. make others unhappyC. tend to please others openlyD. enjoy the pleasure of life 10.We can conclude from the passage that .A. we should pity all such unhappy peopleB. such unhappy people are dangerous to social lifeC. people can get rid of the habit of unhappinessD. unhappy people can not understand happy persons11. If such unhappy persons insist on keeping the habit,the author suggests that peopleshould .A. prevent any communication with themB. show no respect and politeness to themC. persuade them to recognize the bad effectsD. quarrel with them until they realize the mistakesDGive yourself a test. Which way is the wind blowing? How many kinds of wildflowerscan be seen from your front door? If your awareness is as sharp as it could be, you’ll have no trouble answering these questions.Most of us observed much more as children than we do as adults. A child’s day isfilled with fascination, newness and wonder. Curiosity gave us all a natural awareness. But distinctions that were sharp to us as children become unclear; we are numb(麻木的)to new stimulation, new ideas. Relearning the art of seeing the world around us is quite simple, although it takes practice and requires breaking some bad habits.The first step in awakening senses is to stop predicting what we are going to see and feel before it occurs. This blocks awareness. One chilly night when I was hiking in the Rocky Mountains with some students, I mentioned that we were going to cross a mountain stream. The students began complaining about how cold it would be. We reached the stream, and they unwillingly walked ahead. They were almost knee-deep when they realized it was a hot spring. Later they all admitted they’d felt cold water at first.Another block to awareness is the obsession(痴迷) many of us have with naming things.I saw bird watchers who spotted a bird, immediately looked it up in field guides, and said, a "ruby-crowned kinglet" and checked it off. They no longer paid attention to the bird and never learned what it was doing.The pressures of "time" and "destination" are further blocks to awareness. I encountered many hikers who were headed to a distant camp-ground with just enough time to get there before dark. It seldom occurred to them to wander a bit, to take a moment tosee what’s around them. I asked them what they’d seen. "Oh, a few birds," they said. They seemed bent on their destinations.Nature seems to unfold to people who watch and wait. Next time you take a walk, no matter where it is, take in all the sights, sounds and sensations. Wander in this frameof mind and you will open a new dimension to your life.12. According to Paragraph 2, compared with adults, children are more .A. anxious to do wondersB. sensitive to others’ feelingsC. likely to develop unpleasant habitsD. eager to explore the world around them13. What idea does the author convey in Paragraph 3?A. To avoid jumping to conclusions.B. To stop complaining all the time.C. To follow the teacher’s advice.D. To admit mistakes honestly.14. The bird watchers’ behavior shows that they .A. are very patient in their observationB. are really fascinated by natureC. care only about the names of birdsD. question the accuracy of the field guides15. Why do the hikers take no notice of the surroundings during the journey?A. The natural beauty isn’t attractive to them.B. They focus on arriving at the camp in time.C. The forest in the dark is dangerous for them.D. They are keen to see rare birds at the destination.第二节 (共 5 小题;每小题 2 分,满分 10 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。

河南省洛阳市第一高级中学2019-2020学年高二数学12月月考试题(含答案)

河南省洛阳市第一高级中学2019-2020学年高二数学12月月考试题(含答案)

河南省洛阳市第一高级中学2019~2020学年高二12月月考数学试题一、选择题:本题共12个小题,每小题5分,共60分.在每小题给出的四个选项中,只有一个是符合题目要求的.1.已知集合{|1},{|31}=<=<xA x xB x ,则.{|0}A A B x x =< .=B A B R .{|1}=>C A B x x .D A B =∅2.平面内有两定点,A B 及动点P ,设命题甲是:“||||PA PB +是定值”,命题乙是:“点P 的轨迹是以,A B 为焦点的椭圆”,那么 .A 甲是乙成立的充分不必要条件 .B 甲是乙成立的必要不充分条件.C 甲是乙成立的充要条件 .D 甲是乙成立的非充分非必要条件3.命题“[1,2]x ∀∈,2320x x -+≤”的否定是.[1,2]A x ∀∈,2320x x -+> .[1,2]B x ∀∉,2320x x -+>0.[1,2]C x ∃∈,200320x x -+> 0.[1,2]D x ∃∉,200320x x -+> 4.设,a b R ∈,则“a b >”是“||||a a b b >”的.A 充分不必要条件 .B 必要不充分条件 .C 充要条件 .D 既不充分也不必要条件5.双曲线22221(0,0)x y a b a b -=>>. . . .22A y xB y xC yD y =±=±== 6.如果方程22121x y m m +=++表示双曲线,则m 的取值范围是 .(2,1) .(,1) .(1,2) .(2,)A B C D ---∞-+∞7.已知12,F F 是椭圆的两个焦点,过1F 且与椭圆长轴垂直的直线交椭圆于,A B 两点,若2ABF ∆是正三角形,则这个椭圆的离心率为 . 3322A B C D 8.已知12,F F 为双曲线22:1C x y -=的左、右焦点,点P 在C 上,o 1260F PF ∠=,则12||||PF PF =.2 .4 .6 .8A B C D9.焦点在x 轴上的椭圆22214x y b +=的离心率12e =,,F A 分别是椭圆的左焦点和右顶点,P 是椭圆上任意一点,则PF PA 的最大值为.10 .8 .6 .4A B C D10.设,A B 分别为双曲线22221(0,0)x y a b a b-=>>的左、右顶点,P 是双曲线上不同于,A B 的一点,直线,AP BP 的斜率分别为,m n ,则当4b a +取最小值时,双曲线的离心率为22B C D 11.已知双曲线22221(0,0)x y a b a b-=>>的离心率为2,过右焦点且垂直于x 轴的直线与双曲线交于,A B 两点.设,A B 到双曲线的同一条渐近线的距离分别为1d 和2d ,且126d d +=,则双曲线的方程为22222222. 1 . 1 . 1 .19339124412x y x y x y x y A B C D -=-=-=-= 12. 已知12(,0),(,0)F c F c -为椭圆22221(0)x y a b a b+=>>的两个焦点,P 为椭圆上一点且212PF PF c =,则此椭圆离心率的取值范围是11] .[,] .(0,2322A B C D 二、填空题:本题共4个小题,每小题5分,共20分. 13.若“[0,],tan 4x x m π∀∈≤”是真命题,则实数m 的最小值为 .14.已知命题1p :函数ln(y x =是奇函数,2p :函数12y x =为偶函数,则下列四个命题:① 12p p ∨;②12p p ∧;③12()p p ⌝∨;④12()p p ∨⌝.其中,真命题是________.(填序号)15. 一动圆与圆22650x y x +++=外切,同时与圆226910x y x +--=内切,则动圆圆心的轨迹方程为___________.16.已知双曲线2221(0)12x y a a -=>0y -=,左焦点为F ,当点M 在双曲线右支上,点N 在圆22(3)4x y +-=上运动时,||||MN MF +的最小值为__________. 三、解答题:本大题共6个小题,共70分,解答题应写出文字说明、证明过程或演算步骤. 17.(本小题满分10分)命题:p 方程221313x y m m +=--表示焦点在x 轴上的双曲线. 命题q :若存在0[,]44x ππ∈-,使得02tan 0m x -=成立. (1)如果命题p 是真命题,求实数m 的取值范围;(2)如果“p q ∧”为假命题,“p q ∨”为真命题,求实数m 的取值范围.18.(本小题满分12分)已知椭圆2222:1(0)x y C a b a b+=>>的长轴长为8,短轴长为4.(1)求椭圆方程;(2)过(2,1)P 作弦且弦被P 平分,求此弦所在的直线方程及弦长.已知ABC ∆中,2AC =,o120A =,cos B C =.(1)求边AB 的长;(2)设D 是BC 边上一点,且ACD ∆,求ADC ∠的正弦值.20.(本小题满分12分)已知双曲线22122:1(0,0)x y C a b a b-=>>的离心率为2,过右焦点2F 的直线l 交双曲线于,A B 两点,1F 为左焦点. (1)求双曲线的方程;(2)若1F AB ∆的面积等于,求直线l 的方程.21.(本小题满分12分)已知函数x x x f 63)(2+-=,n S 是数列}{n a 的前n 项和,点(,)n n S ()n N *∈在曲线)(x f y =上.(1)求数列}{n a 的通项公式;(2)若1)21(-=n n b ,6n n n b a c ∙=,且n T 是数列}{n c 的前n 项和. 试问n T 是否存在最大值?若存在,请求出n T 的最大值;若不存在,请说明理由.已知椭圆2222:1(0)x y C a b a b +=>>的离心率为12,以原点为圆心,椭圆的短半轴为半径的圆与直线0x y -+=相切.(1)求椭圆C 的方程;(2)设(4,0)P ,,A B 是椭圆C 上关于x 轴对称的任意两个不同的点,连接PB 交椭圆C 于另一点E ,证明直线AE 与x 轴相交于定点Q ;(3)在(2)的条件下,过点Q 的直线与椭圆C 交于,M N 两点,求OM ON 的取值范围.洛阳一高2019-2020学年高二年级12月月考数学参考答案一.选择题1—5 A B C C D 6—10 A B B D C 11-12 B A二.填空题 13.1 14. ①④ 15.2213627x y += 16.7 三.解答题17. 解:(1)命题:p 方程221313x y m m +=--表示焦点在x 轴上的双曲线, 若命题p 为真命题,则310,30m m ->-<,即m 的取值范围是133m <<. ……2分 (2)若命题q 为真命题,则02tan m x =在0[,]44x ππ∈-有解,得22m -≤≤.……4分 又“p q ∧”为假命题,“p q ∨”为真命题,则,p q 两个命题一真一假, ……5分若p 真q 假,则13322m m m ⎧<<⎪⎨⎪<->⎩或,解得23m <<. ……7分若p 假q 真,则13322m m m ⎧≤≥⎪⎨⎪-≤≤⎩或,解得123m -≤≤. ……9分 综上,实数m 的取值范围为1[2,](2,3)3-. ……10分18. 解:(1)由椭圆2222:1(0)x y C a b a b+=>>长轴长为8,短轴长为4,得28,24a b ==,所以4,2a b ==, ……2分所以椭圆方程为221164x y +=. ……4分 (2)设以点(2,1)P 为中点的弦与椭圆交于1122(,),(,)A x y B x y ,则12124,2x x y y +=+=.1122(,),(,)A x y B x y 在椭圆上,所以22111164x y +=,22221164x y +=, ……6分两式相减可得12121212()()4()()0x x x x y y y y +-++-=, 所以AB 的斜率为212112y y k x x -==--, ……8分∴点(2,1)P 为中点的弦所在直线方程为240x y +-=. ……10分由221164240x y x y ⎧+=⎪⎨⎪+-=⎩,得240x x -=,所以02x y =⎧⎨=⎩或40x y =⎧⎨=⎩,所以||AB ==. ……12分 19.(1)因为120A =︒,所以60C B =︒-,由cos B C =得()cos 60B B ︒-1sin )2B B =-3cos sin 22B B =-.……2分即cos B B =,从而tan 3B =, ……4分 又060B ︒<<︒,所以30B =︒, 6030C B =︒-=︒,所以2AB AC ==.……6分 (2)由已知得12AC CD ⋅⋅sin30⋅︒=,所以CD =. ……8分 在ACD ∆中,由余弦定理得2222AD AC CD AC =+-⋅⋅7cos 4CD C =,AD =. ……10分 由正弦定理得sin sin AD ACC ADC=∠,故sin sin AC C ADC AD ⋅∠==. ……12分 20. 解:(1)依题意,2cb a==,1,2a c ==, ∴双曲线的方程为2213y x -=. ……3分 (2)依题意12(2,0),(2,0)F F -,设直线l 的方程为(2)y k x =-. ……4分由2213(2)y x y k x ⎧-=⎪⎨⎪=-⎩得2222(3)4430k x k x k --++=. ……6分 设1122(,),(,)A x y B x y,当k ≠22121222443,33k k x x x x k k ++==--,……8分所以12|||AB x x ==-===. ……10分 又1F 到直线l的距离为d =所以1F AB ∆的面积1||2S AB d =⨯=212|||3|k k =⨯=-, ……11分422890,1,1k k k k +-===±,所以直线l 的方程为(2)y x =±-. ……12分21. (1)因为(,)n n S 在曲线()y f x =上,且2()36f x x x =-+,所以236n S n n =-+. ……1分 当2n ≥时,221363(1)6(1)96n n n a S S n n n n n -=-=-++---=-. ……3分当1n =时,113a S ==适合上式,所以96n a n =-. ……5分(2)因为111(96)()1112(),(32)()2662n n n n n n n n b c a b n ---====-, ① ……6分 所以231111(1)()(3)()(32)()2222nn T n =+-+-++-, ② ……7分234111111()(1)()(3)()(32)()22222n n T n +=+-++-++-, ③ ②-③得 132)21)(23()21)(2()21)(2()21)(2(2121+---++-+-+=n n n n T112)21)(23(211])21(1[)21()2(21+-----=-+=n n n .整理得1)21)(12(-+=n n n T . ④ ……9分所以111111(23)()(21)()()()2222n n nn n T T n n n ++-=+-+=-. ……10分因为1n ≥,所以110,()022nn -<>,所以10n n T T +-<,即1n n T T +<,……11分所以12T T >>…1n n T T +>>>…,所以n T 存在最大值12. ……12分22.解:(1)由题意知12c e a ==,所以22222214c a b e a a -===,即2243a b =.……1分又因为以原点为圆心,椭圆的短半轴为半径的圆与直线0x y -+=相切,所以b ==224,3a b ==. ……2分 故椭圆C 的方程为22143x y +=. ……2分 (2)由题意知直线PB 的斜率存在,设直线PB 的方程为(4)y k x =-. ……3分由22143(4)x y y k x ⎧+=⎪⎨⎪=-⎩得2222(43)3264120k x k x k +-+-=. ……4分 设点11(,)B x y ,22(,)E x y ,则11(,)A x y -,22121222326412,4343k k x x x x k k -+==++.……5分 依题意,直线AE 的方程为212221()y y y y x x x x +-=--.令0y =,得221221()y x x x x y y -=-+. ……6分将11(4)y k x =-,22(4)y k x =-代入,整理得2222121221222(6412)43224()43431328843k k x x x x k k x k x x k -⨯--+++===+--+. 所以直线AE 与x 轴相交于定点(1,0)Q . ……7分 (3)当过点Q 直线MN 的斜率存在时,设直线MN 的方程为(1)y m x =-.……8分由22143(1)x y y m x ⎧+=⎪⎨⎪=-⎩得2222(43)84120m x m x m +-+-=,易知0∆>. ……9分 设(,),(,)M M N N M x y N x y ,则22228412,4343M N M N m m x x x x m m -+==++,22943M N m y y m =-+.则2222222412951253343434344(43)M N M N m m m OM ON x x y y m m m m -+=+=-=-=--++++.……10分因为20m ≥,所以21133044(43)m -≤-<+,所以5[4,)4OM ON∈--.……11分当过点Q直线MN的斜率不存在时,其方程为1x=.解得33(1,),(1,)22M N-或33(1,),(1,)22N M-,此时54OM ON=-.所以OM ON的取值范围是5[4,]4--.……12分。

河南省洛阳市第一高级中学高二数学下学期6月“周练”试卷 文

河南省洛阳市第一高级中学高二数学下学期6月“周练”试卷 文

河南省洛阳市第一高级中学高二数学下学期6月“周练”试卷 文一、选择题(本大题共10小题,每小题5分,共50分)1.a n 是实数构成的等比数列,S n =a 1+a 2+…+a n ,则数列{S n }中 ( ) A.任一项均不为0 B.必有一项为0C.至多有有限项为0D.或无一项为0,或无穷多项为02.在△ABC 中,a=λ,b=3λ,A=45°,则满足此条件的三角形的个数是A.0B.1C.2D.无数个 3.不等式x 2>3x 的解集是 ( )A.{x|x>3}B. {x|x<0或x>3}C. {x|0<x<3}D. R4.等差数列{a n }共有2n+1项,其中奇数项之和为4,偶数项之和为3,则n 的值是( ) A.3 B.5 C.7 D.95.下列不等式的解集是空集的是( )A.x 2-x+1>0B.-2x 2+x+1>0C.2x -x 2>5D.x 2+x>2 6.已知△ABC 的三边长分别为22y x AB +=,22z x AC +=,22z y BC +=,其中x,y,z∈(0,+∞),则△ABC 是( )A.钝角三角形B.直角三角形C.锐角三角形D.以上三种情况均有可能 7.不等式4x-y ≥0表示的平面区域是( )8.某厂的产值若每年平均比上一年增长10%,经过x 年后,可以增长到原来的2倍,在求x 时,所列的方程正确的是( )A.(1+10%)x-1=2B. (1+10%)x =2C. (1+10%)x+1=2D. x=(1+10%)2 9.在△ABC 中,a ,b ,c 分别是角A,B,C 的对边,则a cosB+b cosA=( ) A.a B.b C.c D.不确定10. 若x >1,则22222-+-x x x 有( )A.最小值1B.最大值1C.最小值-1D.最大值-1二、填空题(本大题共4个小题,每小题5分,共20分)11.设P(x,y),其中x,y ∈N ,则满足x+y ≤4的点P 的个数为________.12.在△ABC 中,a ,b ,c 分别是角A,B,C 的对边,若a +b=32,a b=2,A+B=60°,则边c=________. 13.已知正数a ,b 满足ab =a +b +5,则ab 的取值范围是______.ABD14.若一个等差数列前3项的和为34,最后3项的和为146,且所有项的和为390,则这个数列的项数是_______.答 题 卷班级 姓名 分数一.选择题答题卡二.填空题答题卡11_________ 12_________13_________ 14_________三、解答题(本大题分三个小题,每个小题10分,共30分)15.设Sn 是等差数列{a n }的前n 项和,已知331S 与441S 的等比中项为551S ,331S 与441S 的等差中项为1,求等差数列{a n }的通项。

河南省洛阳市第一高级中学高二数学下学期6月“周练”试卷 文.doc

河南省洛阳市第一高级中学高二数学下学期6月“周练”试卷 文.doc

河南省洛阳市第一高级中学高二数学下学期6月“周练”试卷 文一、选择题(本大题共10小题,每小题5分,共50分)1.a n 是实数构成的等比数列,S n =a 1+a 2+…+a n ,则数列{S n }中 ( ) A.任一项均不为0 B.必有一项为0C.至多有有限项为0D.或无一项为0,或无穷多项为02.在△ABC 中,a=λ,b=3λ,A=45°,则满足此条件的三角形的个数是A.0B.1C.2D.无数个 3.不等式x 2>3x 的解集是 ( )A.{x|x>3}B. {x|x<0或x>3}C. {x|0<x<3}D. R4.等差数列{a n }共有2n+1项,其中奇数项之和为4,偶数项之和为3,则n 的值是( ) A.3 B.5 C.7 D.95.下列不等式的解集是空集的是( )A.x 2-x+1>0B.-2x 2+x+1>0C.2x -x 2>5D.x 2+x>2 6.已知△ABC 的三边长分别为22y x AB +=,22z x AC +=,22z y BC +=,其中x,y,z ∈(0,+∞),则△ABC 是( )A.钝角三角形B.直角三角形C.锐角三角形D.以上三种情况均有可能 7.不等式4x-y ≥0表示的平面区域是( )8.某厂的产值若每年平均比上一年增长10%,经过x 年后,可以增长到原来的2倍,在求x 时,所列的方程正确的是( )A.(1+10%)x-1=2B. (1+10%)x =2C. (1+10%)x+1=2D. x=(1+10%)2 9.在△ABC 中,a ,b ,c 分别是角A,B,C 的对边,则a cosB+b cosA=( ) A.a B.b C.c D.不确定10. 若x >1,则22222-+-x x x 有( )A.最小值1B.最大值1C.最小值-1D.最大值-1二、填空题(本大题共4个小题,每小题5分,共11.设P(x,y),其中x,y ∈N ,则满足x+y ≤4的点P 的个数为________.12.在△ABC 中,a ,b ,c 分别是角A,B,C 的对边,若a +b=32,a b=2,A+B=60°,则边c=________. 13.已知正数a ,b 满足ab =a +b +5,则ab 的取值范围是______.ABD14.若一个等差数列前3项的和为34,最后3项的和为146,且所有项的和为390,则这个数列的项数是_______.答 题 卷班级 姓名 分数一.选择题答题卡二.填空题答题卡11_________ 12_________13_________ 14_________三、解答题(本大题分三个小题,每个小题10分,共30分)15.设Sn 是等差数列{a n }的前n 项和,已知331S 与441S 的等比中项为551S ,331S 与441S 的等差中项为1,求等差数列{a n }的通项。

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河南省洛阳市第一高级中学2019-2020学年高二下学期周练(3.15)数学(文)试题1.若直线l 经过点A(1,2),且在x 轴上的截距的取值范围是(-3,3),则其斜率的取值范围是( )A .-1<k<15B .k>1或k<12 C.15<k<1D .k>12或k<-12.已知直线y =kx +1与曲线y =x 3+ax +b 切于点(1,3),则b 的值为( ) A .3 B .-3 C .5D .-53.“m =-1”是“直线mx +(2m -1)y +2=0与直线3x +my +3=0垂直”的( ) A .充分而不必要条件 B .必要而不充分条件 C .充要条件D .既不充分也不必要条件4.直线y =2x +1关于点(1,1)对称的直线方程是( ) A .y =2x -1 B .y =-2x +1 C .y =-2x +3D .y =2x -35.圆x 2+y 2+2x +4y -3=0上到直线x +y +1=0的距离为2的点共有( ) A .1个 B .2个 C .3个 D .4个6.若直线x -y +2=0与圆C :(x -3)2+(y -3)2=4相交于A ,B 两点,则CA →·CB →的值为( ) A .-1 B .0 C .1D .6 7.已知圆C :(x -3)2+(y -4)2=1和两点A(-m ,0),B(m ,0)(m>0),若C 上存在的点P ,使得∠APB =90°,则m 的最大值为( )A .7B .6C .5D .48.如图,在正方体ABCD -A 1B 1C 1D 1中,P 是侧面BB 1C 1C 内一动点.若P 到直线BC 与直线C 1D 1的距离相等,则动点P 的轨迹所在的曲线是( )A .线段B .圆C .双曲线一部分D .抛物线的一部分9.已知椭圆C 1:x 2a 2+y 2b 2=1(a>b>0)与圆C 2:x 2+y 2=b 2,若在椭圆C 1上存在点P ,使得由点P 所作的圆C 2的两条切线互相垂直,则椭圆C 1的离心率的取值范围是( ) A .[12,1) B .[22,32] C .[22,1) D .[32,1)10.已知点P 为双曲线x 216-y 29=1右支上一点,点F 1,F 2分别为双曲线的左、右焦点,M 为△PF 1F 2的内心,若S △PMF 1=S △PMF 2+8,则△MF 1F 2的面积为( ) A .27 B .10 C .8D .611.若圆C :x 2+y 2+2x -4y +3=0关于直线2ax +by +6=0对称,则由点(a ,b)向圆所作的切线长的最小值为________.12.直线l 1和l 2是圆x 2+y 2=2的两条切线.若l 1与l 2的交点为(1,3),则l 1与l 2的夹角的正切值等于________.13.椭圆x 2a 2+y 2b 2=1(a>b>0)的右焦点F(c ,0)关于直线y =bc x 的对称点Q 在椭圆上,则椭圆的离心率是________.14.平面直角坐标系xOy 中,双曲线C 1:x 2a 2-y 2b 2=1(a>0,b>0)的渐近线与抛物线C 2:x 2=2py(p>0)交于O ,A ,B 三点,若△OAB 的垂心为C 2的焦点,则C 1的离心率为________.15.已知实数x ,y 满足x 2+y 2-2y =0.(1)求2x +y 的取值范围;(2)若x +y +c ≥0恒成立,求实数c 的取值范围.16.在直角坐标系xOy 中,以M(-1,0)为圆心的圆与直线x -3y -3=0相切. (1)求圆M 的方程;(2)已知A(-2,0),B(2,0),圆内的动点P 满足|PA|·|PB|=|PO|2,求PA →·PB →的取值范围.17.如图所示,双曲线的中心在坐标原点,焦点在x轴上,F1,F2分别为左、右焦点,双曲线的左支上有一点P,∠F1PF2=π3,且△PF1F2的面积为23,又双曲线的离心率为2,求该双曲线的方程.3月15日文科数学周测答案1.D 2.A 3. A 4.D 5.C 6. B 7.B 8.D 9. C 10. B 11.4 12. 4313.2214.3215.已知实数x ,y 满足x 2+y 2-2y =0. (1)求2x +y 的取值范围;(2)若x +y +c ≥0恒成立,求实数c 的取值范围.解 (1)方法一:圆x 2+(y -1)2=1的参数方程为 ⎩⎪⎨⎪⎧x =cos θ,y =1+sin θ,--------2分∴2x +y =2cos θ+sin θ+1.------------------------------------------------------------3分 ∵-5≤2cos θ+sin θ≤5,--------------------------------------4分 ∴1-5≤2x +y ≤5+1.----------------------------------------------------------------5分方法二:2x +y 可看作直线y =-2x +b 在y 轴的截距,当直线与圆相切时b 取最值,此时|2×0+1-b|5=1.-----------------------------------------------------------------------------3分 ∴b =1±5,∴1-5≤2x +y ≤1+ 5.-------------------------------------------------5分(2)∵x +y =cos θ+1+sin θ=2sin (θ+π4)+1,------------------------7分 ∴x +y +c 的最小值为1-2+c.---------------------------------------------------------8分 ∴x +y +c ≥0恒成立等价于1-2+c ≥0.---------------------------------------------9分 ∴c 的取值范围为c ≥2-1.---------------------------------------------------------------10分16.在直角坐标系xOy 中,以M(-1,0)为圆心的圆与直线x -3y -3=0相切. (1)求圆M 的方程;(2)已知A(-2,0),B(2,0),圆内的动点P 满足|PA|·|PB|=|PO|2,求PA →·PB →的取值范围. 解 (1)依题意,圆M 的半径r 等于圆心M(-1,0)到直线x -3y -3=0的距离,即r =|-1-3|1+3=2.---------------------------------------------------------------------------------------3分 ∴圆M 的方程为(x +1)2+y 2=4.-------------------------------------------------------------4分 (2)设P(x ,y),由|PA||PB|=|PO|2,得 (x +2)2+y 2·(x -2)2+y 2=x 2+y 2,即x 2-y 2=2.---------------------------------------------------------------------------------------6分 ∴PA →·PB →=(-2-x ,-y)·(2-x ,-y)=x 2-4+y 2=2(y 2-1).-------------------------------------------------------------------------8分∵点P 在圆M 内,∴(x +1)2+y 2<4,∴0≤y 2<4,∴-1≤y 2-1<3.∴PA →·PB →的取值范围为[-2,6).------------------------------------------------------------10分 17.如图所示,双曲线的中心在坐标原点,焦点在x 轴上,F 1,F 2分别为左、右焦点,双曲线的左支上有一点P ,∠F 1PF 2=π3,且△PF 1F 2的面积为23,又双曲线的离心率为2,求该双曲线的方程.解 设双曲线的方程为x 2a 2-y 2b 2=1,----------------------------------------1分∴F 1(-c ,0),F 2(c ,0),P(x 0,y 0). 在△PF 1F 2中,由余弦定理,得 |F 1F 2|2=|PF 1|2+|PF 2|2-2|PF 1|·|PF 2|·cos π3-----------------------------------------------------3分 =(|PF 1|-|PF 2|)2+|PF 1|·|PF 2|.即4c 2=4a 2+|PF 1|·|PF 2|.----------------------------------------------------------------------------5分 又∵S △PF 1F 2=23,∴12|PF 1|·|PF 2|·sin π3=2 3.------------------------------------------------------------------------7分 ∴|PF 1|·|PF 2|=8.∴4c 2=4a 2+8,即b 2=2.-----------------------------------------------------------------------------8分 又∵e =c a =2,∴a 2=23.∴所求双曲线方程为3x 22-y 22=1.-------------------------------------------------------------------10分。

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