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第1页共5页2022—2023学年度(下)联合体高二期中检测数学参考答案及评分标准一、单选题(本大题共8小题,每小题5分,共40分)1.D【解析】因为𝑋∼𝑁(3,𝜎2),所以𝑃(𝑋<2)=𝑃(𝑋>4)=15,所以
𝑃(𝑋<4)=1−𝑃(𝑋>4)=45.故选:D.2.B【解析】在等比数列{𝑎𝑛}中,由a2=8,根据等比中项可得𝑎1𝑎3=𝑎22=64,所以log2𝑎1+log2𝑎3=log2𝑎22=log264=6.故选:B.3.A【解析
】由题意知随机变量𝜉服从超几何分布.因为𝜉表示这6本书中理科书籍的本数,所以C86C40C126+C85C41C126=𝑃(𝜉=0)+𝑃(𝜉=1)=𝑃(𝜉≤1).故选:A.4.A【解析】设公差为𝑑,则𝑎2+𝑎3=2𝑎1+3𝑑=8,解得𝑑
=4,所以数列{𝑎𝑛}的通项公式是𝑎𝑛=−2+4(𝑛−1)=4𝑛−6.故选:A.5.C【解析】由𝑃(𝐴)=14,得𝑃(𝐴)=1−𝑃(𝐴)=34.因为𝑃(𝐵𝐴)=𝑃(𝐴)𝑃
(𝐵|𝐴)=𝑃(𝐵)𝑃(𝐴|𝐵),所以𝑃(𝐴|𝐵)=𝑃(𝐴)𝑃(𝐵|𝐴)𝑃(𝐵)=34×1312=12.故选:C.6.A【解析】设𝑎𝑛=𝑎1𝑞𝑛−1.由题意得{𝑎3=16,𝑎2+𝑎4=2×20,
即{𝑎1𝑞2=16,𝑎1𝑞+𝑎1𝑞3=40,解得{𝑎1=4,𝑞=2,(𝑞=12舍去),所以该数列的前n项和为4×(1−2𝑛)1−2=2𝑛+2−4.故选:A.7.D【解析】由题意,得𝑎+𝑏+𝑐+13=1,所以𝑎+𝑏+𝑐=23①.
因为𝐸(𝑋)=(−1)×𝑎+0×𝑏+1×𝑐+2×13=34,所以−𝑎+𝑐=112②.由𝑃(𝑋≥1)=𝑐+13=712,得𝑐=14,依次代入②、①,解得𝑎=16,𝑏=14,所以𝐷(𝑋)=(−1−34)2×16+(0−34)2×14+(1−34)2×14+(
2−34)2×13=1916.故选:D.8.C【解析】不妨设𝑂𝐷1=𝐷𝐶1=𝐶𝐵1=𝐵𝐴1=1,则𝐷𝐷1=0.114,𝐶𝐶1=𝑘1,𝐵𝐵1=𝑘2,𝐴𝐴1=𝑘3.由题意,知𝐷𝐷1+𝐶𝐶1+𝐵𝐵1+𝐴𝐴1𝑂𝐷1+𝐷𝐶1
+𝐶𝐵1+𝐵𝐴1=0.414,即0.114+𝑘1+𝑘2+𝑘34=0.414.设该数列的公差为𝑑.因为𝑘1=0.114+𝑑,𝑘2=0.114+2𝑑,𝑘3=0.114+3𝑑,所以0.114×4+6𝑑4=0.414
,解得𝑑=0.2.故选:C.二、多选题(本大题共4小题,每小题5分,共20分)9.ABD【解析】由题意,得{𝑎1+𝑑=0,7𝑎1+7×62𝑑=𝑎1+3𝑑+12,解得{𝑎1=−1,𝑑=1,故A正确;所以𝑎
𝑛=−1+(𝑛−1)×1=𝑛−2,故B正确;所以𝑎4+𝑎10=2𝑎1+12𝑑=−2+12=10,故C错误;所以𝑆𝑛=(−1)×𝑛+𝑛(𝑛−1)2×1=𝑛2−3𝑛2=12(𝑛−32)2−98.因为𝑛∈𝐍∗,所以当𝑛=1或𝑛=2时
,𝑆𝑛取得最小值,故D正确.故选:ABD.第2页共5页10.BC【解析】因为𝐷(𝑋)=1225,所以𝐷(5𝑋+2)=25𝐷(𝑋)=12,故A错误;由𝑦̂=0.3−0.7𝑥,得样本点(2,−3)
的残差为−3−(0.3−0.7×2)=−1.9,故B正确;由𝑃(𝐵)=0.3,得𝑃(𝐵)=0.7,所以𝑃(𝐵|𝐴)=𝑃(𝐵),即事件A与B独立,故C正确;根据𝜒2=3.712<3.841,故没有95%的把握认
为X与Y有关,故D错误.故选:BC.11.ABD【解析】由𝑎1=1,𝑎𝑛𝑎𝑛+1=2𝑛,得𝑎1𝑎2=2,则𝑎2=2,所以𝑎2𝑎3=4,所以𝑎3=2,故A正确;由𝑎𝑛𝑎𝑛+1=2𝑛,得𝑎𝑛+1𝑎𝑛+2=2𝑛+1,
所以𝑎𝑛+1𝑎𝑛+2𝑎𝑛𝑎𝑛+1=2𝑛+12𝑛=2,即𝑎𝑛+2𝑎𝑛=2,所以数列{𝑎𝑛}的奇数项和偶数项,均是以2为公比的等比数列,𝑎2𝑛=2×2𝑛−1=2𝑛,𝑎2𝑛−1=1×2𝑛−1=2𝑛−1,故B正确;𝑎2𝑛−1+�
�2𝑛=2𝑛−1+2𝑛=3×2𝑛−1,𝑎2𝑛−𝑎2𝑛−1=2𝑛−2𝑛−1=2𝑛−1,故C错误,D正确.故选:ABD.12.AD【解析】设事件𝐴=“向右下落”,则𝐴=“向左下落”,且𝑃(𝐴)=𝑃
(𝐴)=12.因为小球最后落入格子的号码𝑋等于事件𝐴发生的次数,而小球下落的过程中共碰撞小木钉10次,所以𝑋∼𝐵(10,12),所以𝑃(𝑋=1)=C10112×(12)9=5512,𝑃(𝑋=9)=C109(12)9×
12=5512,故A正确,B错误;所以𝐷(𝑋)=10×12×(1−12)=52,故C错误,D正确.故选:AD.三、填空题(本大题共4小题,每小题5分,共20分)13.1【解析】当散点图的所有点都在一条斜率为非0实数的直线上时,它的残差为0,残差的平方和为0,所以它的相关系
数为1.故答案为:1.14.4【解析】由题意,得𝑆𝑘=−3[1−(−2)𝑘]1−(−2)=15,解得𝑘=4.故答案为:4.15.75【解析】设𝑏𝑛={1𝑎𝑛+1},则𝑏3=1𝑎3+1=13,𝑏7
=1𝑎7+1=12.又因为数列{1𝑎𝑛+1}为等差数列,所以2𝑏5=𝑏3+𝑏7=13+12=56,即𝑏5=1𝑎5+1=512,解得𝑎5=75.故答案为:75.16.0.130.46【解析】设事件A为购买的零件是甲厂产品,事件B为购买的零件是乙厂产品,事件C为购买的零件是次品,
则𝑃(𝐴)=0.7,𝑃(𝐵)=0.3,𝑃(𝐶|𝐴)=0.1,𝑃(𝐶|𝐵)=0.2,所以𝑃(𝐶)=𝑃(𝐴)𝑃(𝐶|𝐴)+𝑃(𝐵)𝑃(𝐶|𝐵)=0.7×0.1+0.3×0.2=0.13.因为𝑃(𝐵𝐶)=0.3×0.2=0.06,所以𝑃(𝐵|𝐶)=
𝑃(𝐵𝐶)𝑃(𝐶)=0.060.13≈0.46.故答案为:0.13;0.46.四、解答题(本大题共6小题,共70分)规范解答评分细则17.(1)证明:因为𝑎𝑛+1=2𝑎𝑛+2𝑛+1,所以𝑎𝑛+1−2𝑎𝑛=2𝑛+1,·························
···························2分所以𝑎𝑛+12𝑛+1−𝑎𝑛2𝑛=1,···························································4分即
𝑏𝑛+1−𝑏𝑛=1.·····························································5分又因为𝑏1=𝑎12=2,·········································
················6分所以数列{𝑏𝑛}是首项为2、公差为1的等差数列.·························7分未求出𝑏1扣1分;未说明首项、公差扣1分;第3页共5页(2)解:由(1)知𝑏𝑛=2+(𝑛−1)
×1=𝑛+1,·····················8分所以𝑐𝑛=1(𝑛+1)(𝑛+2)=1𝑛+1−1𝑛+2,·········································9分所以𝑆𝑛=12
−13+13−14+⋯+1𝑛+1−1𝑛+2=12−1𝑛+2.···················10分18.解:(1)记事件𝐴1为“甲在第一轮比赛中胜出”,𝐴2为“甲在第二轮比赛中胜出”,𝐵1为“乙在第一轮比赛中胜出”,𝐵2为“乙在第二轮比赛中胜出”,则𝐴1,𝐴2,𝐵
1,𝐵2相互独立,且𝑃(𝐴1)=45,𝑃(𝐴2)=23,𝑃(𝐵1)=35,𝑃(𝐵2)=34.···················3分因为在两轮比赛中均胜出视为赢得比赛,则𝐴1𝐴2为“甲赢得比赛”,𝐵1𝐵2为“乙赢得比赛”,所以
𝑃(𝐴1𝐴2)=𝑃(𝐴1)𝑃(𝐴2)=45×23=815,···································4分𝑃(𝐵1𝐵2)=𝑃(𝐵1)𝑃(𝐵2)=35×34=920.···································
·5分因为815>920,所以派甲参赛赢得比赛的概率更大.·······················6分(2)记事件𝐷为“甲赢得比赛”,𝐸为“乙赢得比赛”,则“两人中至少有一人赢得比赛”=𝐷∪𝐸.由
(2)知,𝑃(𝐷)=𝑃(𝐴1𝐴2)=815,𝑃(𝐸)=𝑃(𝐵1𝐵2)=920,所以𝑃(𝐷)=1−𝑃(𝐷)=1−815=715,····································
·8分𝑃(𝐸)=1−𝑃(𝐸)=1−920=1120,·········································10分所以𝑃(𝐷∪𝐸)=1−𝑃(𝐷𝐸)=1−𝑃(𝐷)𝑃(�
�)=1−715×1120=223300.故两人中至少有一人赢得比赛的概率为223300.····························12分19.解:(1)由题意,可知𝑞≠1.······································
··········1分因为𝑆6𝑆3=2627,所以𝑎1(1−𝑞6)1−𝑞÷𝑎1(1−𝑞3)1−𝑞=2627,················································3分即1−𝑞61−𝑞3=1+𝑞3=2627,解得
𝑞=−13,····································5分所以𝑎𝑛=−1×(−13)𝑛−1=−1(−3)𝑛−1.····························
·······7分(2)由(1)知𝑎𝑛=−1(−3)𝑛−1,则𝑎𝑛2=19𝑛−1,······························8分所以𝑎𝑛2𝑎𝑛−12=19,且𝑎12=1,············································
··········10分所以数列{𝑎𝑛2}是以1为首项、公比为19的等比数列,·····················11分所以𝑎12+𝑎22+⋯+𝑎𝑛2=1×(1−19𝑛)1−19=98−18×9𝑛−1.·············
·············12分直接给出𝑏𝑛=𝑛+1的扣0.5分;或𝑆𝑛=𝑛2(𝑛+2).未说明“相互独立”扣0.5分.或𝑎𝑛=−(−13)𝑛−1;𝑎𝑛的通项公式未化简的扣0.5分;未说明首项、公比扣1分;或9𝑛−88×9𝑛−1.第4页共5页20.解:(1)正··
·································································2分(2)令𝑡=𝑥2,则552411979iiiitx,···
·································3分552112805iiiiiiyytx,·····················································4分552111111
55iiiittx,······················································5分𝑦=34.·······························
·············································6分所以5152215ˆ5iiiiitybyttt=2805−5×11×34979−5×112=935374=2.5,························7分𝑎̂=𝑦−𝑏̂�
�=34−2.5×11=6.5,············································8分所以𝑦关于𝑡的回归方程为𝑦̂=6.5+2.5𝑡,故𝑦关于𝑥的回归方程为𝑦̂=6.5+2.5𝑥2.·····················
················9分(3)由(2)可得𝑦̂=6.5+2.5𝑥2.令𝑥=6,则𝑦̂=6.5+2.5×62=96.5.·····································
11分故预测2023年该公司新能源汽车的年销售量为96.5万辆.·············12分21.解:(1)恰好取到3种颜色的球的概率𝑃=C21×C21×C21C63=25.·············
··3分(2)随机变量𝑋的可能取值为4,5,6,7,8.·························4分当𝑋=4时,取出2个红球和1个白球,则𝑃(𝑋=4)=C22×C21C63=110;·····························
························5分当𝑋=5时,取出2个红球和1个黑球或1个红球和2个白球,则𝑃(𝑋=5)=C22×C21+C21×C22C63=15;······································
·········6分当𝑋=6时,取出1个红球和1个白球和1个黑球,则𝑃(𝑋=6)=C21×C21×C21C63=25;··················································
··7分当𝑋=7时,取出1个红球和2个黑球或2个白球和1个黑球,则𝑃(𝑋=7)=C21×C22+C22×C21C63=15;················································8分当𝑋=8时,取出2个黑球
和1个白球,则𝑃(𝑋=8)=C22×C21C63=110,·······················································9分所以随机变量𝑋的分布列如下:·······································
10分𝑋45678P110152515110所以𝐸(𝑋)=4×110+5×15+6×25+7×15+8×110=6.············12分未给出随机变量X的所有取值的扣1分;未写出“当X=4时,2个
红球和1个白球”等文字情况的不扣分;未写出𝐸(𝑋)的计算过程的扣0.5分.第5页共5页22.(1)证明:因为𝑇𝑛为数列{𝑆𝑛}的前n项和,当𝑛=1时,𝑆1+𝑇1=𝑆1+𝑆1=2𝑆1=2,则𝑆1=1;·······
············1分当𝑛≥2时,𝑇𝑛−𝑇𝑛−1=𝑆𝑛.𝑆𝑛+𝑇𝑛=2①,𝑆𝑛−1+𝑇𝑛−1=2②,······································2
分①-②,得2𝑆𝑛=𝑆𝑛−1(𝑛≥2),则𝑆𝑛𝑆𝑛−1=12(𝑛≥2),·····················3分所以数列{𝑆𝑛}是首项为1、公比为12的等比数列.···························4分(2)解:由(1)可得,
𝑆𝑛=(12)𝑛−1.当𝑛=1时,𝑎1=𝑆1=1;······················································5分当𝑛≥2时,𝑎𝑛=𝑆𝑛−𝑆𝑛−1=
(12)𝑛−1−(12)𝑛−2=−(12)𝑛−1,·········6分显然对于𝑛=1不成立,所以𝑎𝑛={1,𝑛=1,−(12)𝑛−1,𝑛≥2.·····································
·······7分当𝑛=1时,𝐴1=𝑎1=1;····················································8分当𝑛≥2时,𝐴𝑛=1−[2×12+3×(
12)2+⋯+𝑛(12)𝑛−1]③,则12𝐴𝑛=12−[2×(12)2+3×(12)3+⋯+𝑛⋅(12)𝑛]④.·················9分由③−④,得12𝐴𝑛=12−[1+(12)2+(1
2)3+⋯+(12)𝑛−1−𝑛⋅(12)𝑛]=12−{1+14[1−(12)𝑛−2]1−12−𝑛⋅(12)𝑛}=(𝑛+2)⋅(12)𝑛−1,·································10分
所以𝐴𝑛=(𝑛+2)⋅(12)𝑛−1−2.···········································11分又因为𝑛=1时,𝐴1=3×1−2=1.所以𝐴𝑛=(𝑛+2)⋅(12)𝑛−1−2.·············
································12分未讨论𝑛=1的情况的扣1分;未说明首项、公比扣1分;未讨论𝑛=1的情况的扣1分;𝑎𝑛的通项公式未归纳成分段形式的,扣0.5分;③−④的最后结果对,计算过程错误的扣0.5分;最后结果未化简的扣0.5分;未给出𝑛=1时
𝐴1的值的扣1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