【文档说明】福建省宁德市2021-2022学年第一学期期末高二质量检测数学试卷参考答案.docx,共(11)页,441.668 KB,由管理员店铺上传
转载请保留链接:https://www.doc5u.com/view-a1b86084ce49628c2629e74b14a91581.html
以下为本文档部分文字说明:
宁德市2021-2022学年度第一学期期末高二质量检测数学参考答案及评分标准说明:一、本解答指出了每题要考查的主要知识和能力,并给出了一种或几种解法供参考,如果考生的解法与本解法不同,可根据试题的主要考查内容比照评分标准制定相应的评分细则.二、对计算题,
当考生的解答在某一部分解答未改变该题的内容和难度,可视影响的程度决定后继部分的给分,但不得超过该部分正确解答应给分数的一半;如果后继部分的解答有较严重的错误,就不再给分.三、解答右端所注分数,表示考生正确做到
这一步应得的累加分数.四、只给整数分数,选择题和填空题不给中间分.一、单项选择题:本题共8小题,每小题5分,共40分.在每小题给出的四个选项中,只有一个选项是符合题目要求的.1.A2.C3.B4.D5.A6.C7.B8.C二、多项选择题:本题共4小题,每
小题5分,共20分.在每小题给出的选项中有多项符合题目要求,全部选对的得5分,部分选对的得2分,有选错的得0分)9.ABC10.BC11.ABC12.BCD三、填空题:(本大题共4小题,每小题5分,共20分.把答案填在答题卡的相应位置)13.3yx=14.30.15.22
2nn−+16.31−(答案为423−不扣分)四、解答题:本大题共6小题,共70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10分)解:选①:012(1)1372nnnnnCCCn−
++=++=..................................................................2分8n=或9n=−(舍去)·····························································
··············4分选②:依题意得2172nnCC=···············································································2
分即(1)722nnn−=得8n=···················································································
·················4分选③:偶数项的二项式系数之和为1351...2128nnnnCCC−+++==·····························2分8n=解得··········
·······················································································4分(1)82()xx−展开式的通项公式为()83821882(2)rrrrrrrTCx
Cxx−−+=−=−...................6分令8312r−=,得2r=·················································································7分展开式中x的项的系数为112·
····································································8分(2)展开式中二项式系数最大的项为422816=1120Cx
x−−··································10分18.(本小题满分12分)解:法一:(1)ABQ边上的中线所在的直线的方程为1x=可设(1,)Cm················
········································································1分ACQ边上的高所在的直线方程为26yx=−+,其斜率为-
2(2)(2)12ACmk−=−=−,····································································3分解得:1m=···········
··············································································4分(1,1)C··························
····································································5分(2)(1,0),(3,0),(1,1),ABC−Q(1,4)D−1,22
ACADkk==−············································································6分1ACADkk=−ACADkk⊥··················
······································································8分1,22BCBDkk=−=BCBDkk⊥········································
················································10分,,,ABCD在以CD为直径的圆上.························································12分法二:(1)同法一.
..........................................................................................................5分(2)(1,0),(3,0),(1,1),ABC−Q(1,4
)D−1,22ACADkk==−·············································································7分1ACADkk=−,ACADkk⊥·······
················································································9分ACDV的外接圆的圆心为3(1,)2−,半径为52ACDV的外接圆的方程为22
325(1)()24xy−++=····································11分22325(31)(2)24−++=Q,即(3,0)B满足上述方程,,,ABCD四点共圆.·············································
···························12分法三:(1)同法一...................................................................................................
........5分(2)设ABC外接圆的方程为:222()()xaxbr−+−=·······························6分将三点(1,0),(3,0),(1,1)ABC−分别代入圆的方程:222222222(1)(0)(3
)(0)(1)(1)abrabrabr−−+−=−+−=−+−=····7分解得2132254abr==−=·····················································
·····························10分(1,0),(3,0),(1,1)ABC−的外接圆方程:22325(1)()24xy−++=···················11分(1,4)D−Q满足上述方程,,,,ABCD四点共圆.··········
···························································12分法四:(1)同法一......................................................
.....................................................5分(2)设ABC外接圆的方程为:22220(40)xyDxEyFDEF++++=+−··········6分将三点(1,0),(3,0),(1,1)ABC−代入圆的方程:10009
0300110DFDFDEF+−++=++++=++++=··············7分解得233DEF=−==−...........................................
.......................................................................10分ABC的外接圆方程:222330xyxy+−+−=····
····································11分(1,4)D−Q满足上述方程,,,ABCD四点共圆.···············································
·························12分19.(本小题满分12分)解:(1)设na的公差为d,设nb的公比为q,.....................................................1分则22
2226324dqdq+=++=+·············································································3分0qQ2,2dq==·················
·····························································4分2nan=........................................................
...............................................................5分2nnb=····················································
······································6分(2)2,2nnnnnc=为奇数;,为偶数.·······························································
·············7分2112342021..Tcccccc=+++++···························································8分246202122322522221=++++++++
L246202[13521](2222)=+++++++++LL·····································9分123102[13521](4444)=+++++++++LL104242(41)3=+−11722433=+········
·················································12分(答案是104242(41)3+−或41950263不扣分))20.(本小题满分12分)解:(1)设椭圆
C的该方程:22221(0)yxabab+=......................................................1分则222232acaabc===+············
···································································2分21ab==··············································
···················································4分椭圆C的方程:2214xy+=·····························································5分
(2)解法一:1(0,)2P,设1122(,),(,)AxyBxy,··············································6分联立2221422301122xyxxyx+=+−==+
··························································7分解得:1172x−−=,2172x−+=·······················································9分所以,171
7(,)24A−−−,1717(,)24B−++2217171355(0)(),2424PA−−−+=−+−=··································10分2217171355(0)(),2424PB−++−=−+−=···
·······························11分35535515448PAPB+−==···················································12分解法二:1(0,)2P,设1122(,),(,)AxyBxy,··
····················································6分2211115(0)(),22PAxyx=−+−=·······················································7分
2222215(0)(),22PBxyx=−+−=························································8分联立2221422301122xyxxyx+=+−==+···················
········································9分1232xx=−······················································································10分12515=
48PAPBxx=g...............................................................................................12分21(本小题满分12分)解:(1)Q111ab−=,
111ab+=,数列nnab−是公比为12的等比数列...................................................................1分112nnnab−−=............................
.......................................................................2分111nnnnaabb++−=−+Q11()1nnnnabab+++−+=
·································································4分nnab+是1为首项,1为公差等差数列············································5分nnabn+=·
···············································································6分(2)由(1)知112nnnab−−=,nnabn+=1221()()2nnnnnnnabababn−−=+
−=..........................................................................7分所以01211111123.........2222nnTn−=++++++
()12311111111231222222nnnTnn−=++++−+L,所以0234111111112222222nnnTn−=+++++−
L······················8分即11112222nnnTn−=−−,得2111422nnnTn−−=−−...............................
............................................................10分所以21114422nnnTn−−=−−·········
·············································11分所以4t······················································
································12分22.(本小题满分12分)解:法一(1)设(),Pxy,Q动点P到直线2x=−的距离比到点()1,0F的距离大1PF等于P到直线1x=−的距离····
····················································1分根据抛物线的定义知,曲线E是以()1,0F为焦点,直线1x=−为准线的抛物线.······························
······························2分故曲线E的方程为24yx=.·······························································4分(2)显然,OM
ON斜率存在,分别设,OMON的直线方程为12,ykxykx==·········5分联立21144yxykykx===,所以21144(,)Mkk,···········································6分同理得:22244(
,)Nkk··········································································7分因为2211224444(,),(,),(2,0)MNQkkkk三点共线//QMQNuuuruuur21144(2,)
QMkk=−uuur,22244(2,)QNkk=−uuur2221124444(2)(2)kkkk−=−122kk=−············································
·······································8分()222111121xyxkykx−+==+=,所以1221122(,)11kAkk++,同理得:2222222(,)11kBkk++·································
··························9分若存在满足题设的定点,由抛物线与圆的对称性知定点必在x轴上,设定点为(,0)Tm由1221122(,)11kAkk++,2222222(,)11kBkk++,(,0)Tm三点共线//TATBuuruur
1221122(,)11kTAmkk=−++uurQ,2222222(,)11kTBmkk=−++uur21222212212222()1111kkmmkkkk−=−++++,·····································
·····10分122kk=−Q得()()122323mkmk−=−,即4()1223()0mkk−−=即恒成立,···················11分120kk−Q23m=,直线AB过定点2
(,0)3T······················································12分(备注:能写对定点坐标的给1分)法二:(1)设动点(,)Pxy依题意有:2221(1)xxy+−=−+····························
··························2分由几何直观知0x所以,221(1)xxy+=−+化简得:24yx=...........................................................................
........................4分(2)1o当直线AB垂直于x轴时,由对称性可知MN也垂直于x轴,所以(2,22)M,(2,22)N−,,OMON的直线方程为22yx=,22yx=−,()221124(,2)3322xyAyx−+==,同理得:24(,2)33B−,
所以直线AB的方程为23x=···································································································5分2o当直线AB不垂直于x轴
时,设AB的方程为ykxm=+,()11,Axy,()22,Bxy,联立()2222211(1)(22)0xykxkmxmykxm−+=++−+==+122212202211kmxxkmxxk
−+=−+=+·································6分设,OMON的直线方程为11yyxx=,22yyxx=,则2111144yxxyyyxyx===,所以21121144(,
)xxMyy,2222244yxxyyyxyx===,所以22222244(,)xxNyy,··············································7分因为21121144
(,)xxMyy,22222244(,)xxNyy三点共线//PMPNuuuruuur21121144(2,)xxPMyy=−uuur,22222244(2,)xxPNyy=−uuur····················
························9分2212122221124444(2)2xxxxyyyy−=−12122yyxx=−·······································································
··············10分()()212212121212121211()()2kxmkxmyymmmkkkkmxxxxxxxxxx++==++=+++=−()212222212122212xx
mkmkkmkkmkxxxxm+−++=+++=−化简得23mk=−,··········································································11分代
入直线AB的方程为2()3ykx=−,所以直线AB恒过2,03综合1o,2o得直线AB恒过2,03·······················································12分法三:(1)设动点(,)Pxy依题意有
:2221(1)xxy+−=−+······················································2分当2x−时,得221(1)xxy+=−+化简得:24yx=(0)x当2x−时,得223(1)xxy−−=−+化简得:2880yx=+,
舍去所以,24yx=··············································································4分(注:若未舍去288yx=+,扣1分)(2)显然直线AB不平行于x轴,可设AB的方程为xmyn=+,()11,Ax
y,()22,Bxy,联立()2222211(1)(22)20xymymnnynnxmyn−+=++−+−==+1222122022121nmnyymnnxxm−+=−+−=
+························5分设,OMON的直线方程为11yyxx=,22yyxx=2111144yxxyyyxyx===,所以21121144(,)xxMyy,
············································6分2222244yxxyyyxyx===,所以22222244(,)xxNyy,·········································
··7分因为21121144(,)xxMyy,22222244(,)xxNyy三点共线//PMPNuuuruuur21121144(2,)xxPMyy=−uuur,22222244(2,)xxPNyy=−uuur·································
··········9分2212122221124444(2)2xxxxyyyy−=−12122yyxx=−··········································································
··········10分()()()12121222121212122yyyyyyxxmynmynmyymnyyn===−+++++化简得23n=,······································
········································11分代入直线AB的方程为23xmy=+,所以直线AB恒过2,03···················12分获得更多资源请扫码加入享学资源网微信公众号www.xiangxue100.com