【文档说明】山西大学附属中学20192020学年高二下学期5月月考试题数学(文)答案.docx,共(4)页,174.672 KB,由小赞的店铺上传
转载请保留链接:https://www.doc5u.com/view-3b30833e05d4ff25d5a1389244748313.html
以下为本文档部分文字说明:
山西大学附中2019—2020学年第二学期高二年级5月模块诊断数学答案考查时间:120分钟满分:150分考查内容:极坐标参数方程,不等式,集合和函数一、选择题(5×12=60分)二、填空题(5×4=20分)13.214.),2(
+15.516.]29,417[三、解答题(共70分)17.(满分10分)(1)根据指数幂的运算性质化简可得113202581()9274e−−−++()13132252=1233−−−−+
.............................3分52=12233−−+=.............................5分(2)根据对数的运算性质化简可得lg8lg125lg2lg5lg10lg0.1+−−()()1lg8125lg251
lg10lg102−−=.............................3分()314112−==−−............................5分18.(满分12分)根据题意,
集合A={x|x2+4x=0}={0,﹣4},若A∩B=B,则B是A的子集,....3分且B={x|x2+2(a+1)x+a2﹣1=0},为方程x2+2(a+1)x+a2﹣1=0的解集,分4种情况讨论:①B=∅,△=[2(a+1
)]2﹣4(a2﹣1)=8a+8<0,即a<﹣1时,方程无解,满足题意........................5分123456789101112ADBCDBDCBABA②B={0},即x2+2(a+1)x+a2﹣1=0有两个相等的实根0,则有a+1=0且a2﹣1=0,解可得a=﹣1,..
.............................7分③B={﹣4},即x2+2(a+1)x+a2﹣1=0有两个相等的实根﹣4,则有a+1=4且a2﹣1=16,此时无解,..................................................
....9分④B={0、﹣4},即x2+2(a+1)x+a2﹣1=0有两个的实根0或﹣4,则有a+1=2且a2﹣1=0,解可得a=1,..........................................................11分综合可得:a=1
或a≤﹣1..................................................12分19.(满分12分)(1)由2222cos3sin12+=,将x=ρcosθ,y=ρsinθ代入得到2x+32y=12,...........2分所以曲线C的直角
坐标方程为2x+32y=12,P的极坐标为()2,,化为直角坐标为(-2,0)由直线l的参数方程为:22222xtyt=−+=(t为参数),知直线l是过点P(-2,0),且倾斜角为4的直线,把直线的参数方程代入曲线C得,2240t
t−−=................................3分由韦达定理可得:12+=2tt,12=-4tt.....................................4分因为120tt,所以1212-
=2PMPNtttt−=+=..............................6分(2)由曲线C的方程为221124xy+=,不妨设曲线C上的动点()232Qcossin,,...................
...........7分则以P为顶点的内接矩形周长l()4232cossin=+,...............................9分16032sin=+
<<.............................10分又由sin(θ3+)≤1,则l≤16;...................................11分因此该内接矩形周长的最大值为16....................................12分2
0.(满分12分)(1)()22afxxax=++−,()()22afxxafxx−=−−+−=−,故220a−=,2a=.........................2分当2a=时,()2fxxx=+在(0,)+上先
减后增,排除;.......................3分当2a=−时,()2fxxx=−在(0,)+上单调递增,满足,故2a=−...............4分(2)()()22log101xaf+−+=,即()21log1xa+
=−,.............5分画出函数图像,如图所示:...................................8分011a−,故()0,1a.............................
....9分()()22log1log1mn=−++,故()()111mn++=,即111mn+=−....................12分21.(满分12分)(1)因为函数()logafxx=在()0,+上为减函数,所以P真:01a.因为关于x的不等式()223
10xax+−+有实数解,......................1分Q真:2(23)40a=−−,解得52a或102a......................2分因为PQ为真且PQ为假,所以P,Q一真一假.当P真Q假时,01111521122aaa
a或...............................4分当P假Q真时,15512022aaaa或.......................
...............6分综上112a或52a.(2)设2()(23)1gxxa=+−+,因为函数()2231ylgxax=+−+的值域包含区间1,3−,等价于()22311minylgxax-=+−+();..
.................................8分等价于min1()10gx,.....................................9分即24(23)1410a−−,...............................10分21
8(23)5a−,解得1531010a+或1531010a−...............................12分22.(满分12分)(I)1abc===,不等式()5fx,即114xx−++当1x−时,11421xxx−−−−
−...................................2分当11x−时,11411xxx−+−−.......................................4分当1x时,11412xxx−++
................................6分解集为()2,2−(II)()fxxbxca=−+++()()xcxba+−−+bca=++..................7分a0,b
0,c0()min1fxabc=++=.................8分149abbcca++=+++149abbcca+++++()abc++11492abbcca=+++++()abbcac+++++..............
.................................10分22211232abbcca=+++++()()()222abbcca+++++
211232abbccaabbcca++++++++()1818abc==++.....................................12分