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学科网(北京)股份有限公司成都石室中学2024~2025学年度上期高2025届十月月考数学参考答案一、选择题:本大题共8小题,每小题5分,共40分。在每小题给出的四个选项中,只有一项是符合题目要求的,
请把正确的选项填涂在答题卡相应位置.1.已知集合1,2,4A=,2{|20}BxNxx=+−,则AB=A.2,1,0,1,2,4−−B.0,1,2,4C.1,2,4D.1【答案】B【解析】{0,1}B=,故{0,1,2,4}AB=,故选B.2.202
4年巴黎奥运会中国代表队获得金牌榜第一,奖牌榜第二的优异成绩.首金是中国组合黄雨婷和盛李豪在10米气步枪混合团体赛中获得,两人在决赛中14次射击环数如右图,则A.盛李豪的平均射击环数超过10.6B.黄雨婷射击环数的第80百分位数为10.65C.盛李豪射击环数
的标准差小于黄雨婷射击环数的标准差D.黄雨婷射击环数的极差小于盛李豪射击环数的极差【答案】C【解析】盛李豪的射击环数只有两次是10.8环,5次10.6环,其余都是10.6环以下,所以盛李豪平均射击环数低于10.6,故A错误;由于140.811.2=,
故第80百分位数是从小到大排列的第12个数10.7,故B错误;由于黄雨婷的射击环数更分散,故标准差更大,故C正确;黄雨婷射击环数的极差为10.8-9.7=1.1,盛李豪的射击环数极差为10.8-10.3=0.5,
故D错误.故选C.3.已知0.10.6a=,0.6log0.3b=,0.6log0.4c=,则a,b,c的大小关系为A.bcaB.abcC.cbaD.acb【答案】A【解析】由于0.6logyx=在(0,)+单调递减,故0.6l
og0.61bc=,又因为1a,所以bca,故选A.4.已知实数a,b,c满足abc,且0abc++=,则下列说法正确的是A.22abcbB.222acca+C.||||abD.0abbc+【答案】C9.69.
79.89.91010.110.210.310.410.510.610.710.810.91234567891011121314射击成绩图盛李豪黄雨婷学科网(北京)股份有限公司【解析】由题,0,0ac,取1,0,1abc===−,则22abc
b=,故A错误;2522acca+=−,故B错误;0abbc+=,故D错误;因为22()()()0abababcab−=+−=−−,所以22ab,即||||ab,故C正确.故选C.5.“函数2()ln(2
2)fxxax=−+的值域为R”的一个充分不必要条件是A.[2,2]−B.(0,2C.(,2[2,)−+UD.[2,)+【答案】D【解析】因为函数2()ln(22)fxxax=−+的值域为R,所以在方程2220xax−+=中,0,即2480a−,解得2a或2a−,从而[2,
)+是“函数2()ln(22)fxxax=−+的值域为R”的充分不必要条件.故选D.6.核燃料是重要的能量来源之一,在使用核燃料时,为了冷却熔化的核燃料,可以不断向反应堆注入水,但会产生大量放射性核元素污染的冷却水,称为核废水.核废水中含有一种放射性
同位素氚,它有可能用辐射损伤细胞和组织,影响生物的繁殖和生态平衡。已知氚的半衰期约为12年,则氚含量变成初始量的110000大约需要经过()年.(lg20.3010)A.155B.159C.162D.1
66【答案】B【解析】设氚含量变成初始量的110000大约需要经过t年,则1211()210000t=,121log1210000t=,即36159lg2t=,故选B.7.若函数()yfx=的图象如图1所示,则如图2对应的函数可能是A.(12)yfx=
−B.1(1)2yfx=−C.(12)yfx=−−D.1(1)2yfx=−−【答案】A【解析】由()yfx=的定义域为(1,)−+知,1(1)2yfx=−中111,42xx−−,不符合图2,故排除B,D;对于C,
当12x=时,(0)0yf=−,不满足图2,故C错误;将函数()yfx=的图关于y=轴对称,得到()yfx=−的图,向右平移1个单位得到(1)yfx=−的图,最后纵坐标不变,横坐标变为原来的一半,得到函数(12)yfx=−的图可能为图2,故选A.8.已知函数11,0,()2221,
0.xxxfxx+=−,则方程()(3)2fxfx+−=的所有根之和为学科网(北京)股份有限公司A.0B.3C.6D.9【答案】C【解析】方程()(3)2fxfx+−=的根为函数()yfx=和2(3)yfx=−−的图象交点横坐标,由函数11,0,()2221,0.xxxf
xx+=−得,31,3,2(3)232,3,xxxyfxx−=−−=−如下图所示,两函数图象共有4个交点,且由于两个函数图象关于点3(,1)2中心对称,故方程()(3)2fxfx+−=的所有根之和为6,故选C.二、选择题:本
大题共3小题,每小题6分,共18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6分,部分选对的得部分分,有选错的得0分,。9.已知函数()fx的定义域为R,()()()22fxyfxfy+=+,则A.()00f=B.()11f=C.𝑓(𝑥)是奇函数D.𝑓(𝑥
)在R上单调递增【答案】AC【解析】由()()()22fxyfxfy+=+知,当0xy==时,()()300ff=,即()00f=,故A正确;若()fxx=−,则()fx满足条件()()()22fxyfxfy+=+,但()11f=−,且𝑓(𝑥)是在R上
单调递减,故B,D错误;当,xtyt=−=时,()()()2ftftft=−+,即()()fttf−=−,故C正确,故选AC.10.已知复数12z,z的共轭复数分别为21,zz,则下列命题为真命题的是A.1
212zzzz+=+B.1212zzzz=C.若12zz0−,则12zzD.若2221212zzzz=++,则2121zzzz0+=【答案】ABD【解析】设12i,izabzcd=+=+且,,,Rabcd,则12i,iabczzd=
−=−,12ii()izzabcdacbd+=+++=+++,12()iaczbdz+=+−+所以12()iaczbdz−=+++,所以1212zzzz+=+,故A正确;学科网(北京)股份有限公司12i)(i)()i(()zzabcdacbdbcad++=−−+=,12i)(i)()
i(()zzabcdacbdbcad−−=−−+=,故B正确;当1212i,2izz=+=时,满足1210zz−=,但不能得出12zz,故C错误;222121212121211221212121221()()()()zzzzzzzzzzzzzzzzz
zzzzzzz+++===++=++++++,故11220zzzz+=,故D正确,故选ABD.11.设函数()()()lnfxxaxb=++,则下面说法正确的是A.当0,1ab==时,函数()fx在定义域上仅有一个零点B.当0,0ab==时,函数()fx在(1,)+上单调递增C.若
函数()fx存在极值点,则abD.若()0fx,则22ab+的最小值为12【答案】ABD【解析】当0,1ab==时,()ln(1)fxxx=+,由()0fx=得,0x=,函数()fx在定义域上仅有一个零点,故A正确;当0ab==时,函数()lnfxxx=,当1x时,(
)ln10fxx=+,故函数()fx在(1,)+上单调递增,故B正确;()ln()ln()1xaabfxxbxbxbxb+−=++=+++++,当ab时,函数()fx在定义域上单调递增,且当xb→−时,()fx→−,当x→+时,()fx→+,此时函数()fx
存在零点0x,即函数函数()fx在0(,)bx−上单调递减,在0(,)x+上单调递递增,故此时函数()fx存在极值点,当ab时,()2212()()abxbafxxbxbxb−+−=−=+++,故函数()fx在(,2)bab−−上单
调递减,在(2,)ab−+上单调递递增,故()()2ln()2fxfabab−=−+,故当21ebab+时,函数()fx存在零点,函数()fx存在极值点,综上,当函数()fx存在极值点时,21ebab+或ab,故C
错误;对于D,()()ln0xaxb++恒成立,当()0fx=时,xa=−或1xb=−,当且仅当两个零点重合时,即1ab−=−,函数()fx在(1,)aa−−−上单调递学科网(北京)股份有限公司减,在(,)a−+上单调递增,满足()()ln0xaxb+
+,则22212212abbb+=−+,当12b=时取“=”,故D正确,故选ABD.三、填空题:本题共3小题,每小题5分,共15分。12.若函数2()23fxxkx=++在[1,2]上单调,则实数k的取
值范围为_____.【答案】8k−或4k−【解析】函数2()23fxxkx=++的对称轴为04kx=−,故当24k−或14k−时,函数()fx在[1,2]上单调,即8k−或4k−,故答案为8k−或4k−.
13.若()yfx=是定义在R上的奇函数,()(2)fxfx=−,(1)2f=,则(1)(2)(3)(2025)ffff+++=________.【答案】2【解析】因为()yfx=是定义在R上的奇函数,故()()fxfx−=−,又因为()(2)fxfx=−,所以(2)(
)fxfx−=−−,故(2)()fxfx+=−,所以,(4)(2)()fxfxfx+=−+=,即()yfx=的周期为4,由于()yfx=为定义在R上的奇函数,故(0)0f=,(2)(0)0ff==,(3)(1)(1)2fff=−=−=−,故(
1)(2)(3)(4)0ffff+++=,(1)(2)(3)(2025)ffff+++=506[(1)(2)(3)(4)](1)2fffff++++=,故答案为2.14.若过点1,)b(作曲线exyx=的切线有且仅有两条,则b的取值范围是.【答案】25[0
,){}ee−【解析】设切点为000(,)xxxe,()(1)xfxxe=+,故切线方程为00000(1)()xxyxexexx−=+−,将1,)b(代入切线方程得000200000(1)(1),(1)xxxbxexexbxxe−=+−=−+,令2()(1)xgxxxe
=−+,则2()(2)(1)(2)xxgxxxexxe=−−=−−+,故()gx的单调减区间(,2),(1,)−−+,增区间是(2,1)−.当x→−时,()0gx→,当x→+时,()gx→−,25(1),(2)gege=−=−,当yb=与()ygx=有且仅有两个交点时,25[0,)
{}bee−,故答案为25[0,){}ee−.四、解答题:本题共5小题,共77分。解答应写出文字说明、证明过程或演算步骤。学科网(北京)股份有限公司15.(13分)已知函数()1ln1kxfxx−=−为奇函数.(1)求实数k的值;(2)若函
数()()2xgxfxm=−+,且()gx在区间2,3上没有零点,求实数m的取值范围.【答案】(1)1−;(2)(,4ln3)(8ln2,)m−−−+【解析】(1)因为()1ln1kxfxx−=−是奇函数,所以()()fxfx−=−,·······
·········1分即111lnlnln111kxkxxkxxx+−=−−=−−−−,···························································3分所以1111kxxkxx+=−−−−,故222
11kxx−=−,则1k=,·······································5分当1k=时,111xx−=−−显然不成立;经验证:1k=−符合题意;所以1k=−;···········6分(2)由1()ln21xxgxmx+=−+−,22()2ln21xgx
x=−−−,··························8分当[2,3]x时,()0gx,故()gx在[2,3]上单调递减.································9分故()[ln28,ln34]gxmm−+−+.····················
········································10分因为()gx在区间2,3上没有零点,所以ln280m−+或ln340m−+········12分所以(,4ln3)(8ln2,)m−−−+·····················
···································13分16.(15分)已知三棱锥D-ABC,D在平面ABC上的射影为△ABC的重心O,15ACAB==,24BC=.(1)证明:BC⊥AD;(2)E为AD上靠近A的三等分
点,若三棱锥D-ABC的体积为432,求二面角ECOB−−的余弦值.【答案】(1)见解答;(2)43333−【解析】(1)如图所示,连结AO并延长交BC于M,因为O为△ABC的重心,所以M是BC的中点,·····
·············································1分又因为ACAB=,所以由等腰三角形三线合一可得AMBC⊥,········2分因为D在平面ABC上的射影为O,
所以OD⊥平面ABC,·············3分又BC平面ABC,所以ODBC⊥,·······································4分又,,AMODOAMOD=平面AMD,所以BC⊥平面AMD,·······5
分又AD平面AMD,所以BCAD⊥,···························································6分(2)由(1)知AMBC⊥,OD⊥面ABC,过M作
z轴平行于OD,则z轴垂直于面ABC,如图以,MAMB为x轴,y轴,建立空间直角坐标系,·····································7分ABCDOE学科网(北京)股份有限公司在ABC中,15ACAB==,24BC=由(1)知,AMBC⊥,故229AMABBM
=−=,11082ABCSAMBC==,8分所以三棱锥A-BCD的体积为1110843233ABCSODOD==,则12OD=因为O为△ABC的重心,故133OMAM==,··································9分则()()()()
()0,12,0,0,12,0,3,0,0,9,0,0,3,0,12CBOAD−,()()()6,0,0,6,0,12,3,12,0OAADOC==−=−−因为E为AD上靠近A的三等分点,所以()12,0,43AEAD==−,故()14,0,43
OEOAAD=+=··································································10分设(),,nxyz=为平面ECO的一个法向量,则4403120nOE
xznOCxy=+==−−=,取4x=,则1,4yz=−=−,故()4,1,4n=−−,·········································12分易得()0,0,1m=是平面COB的一个法向量,
·················································13分设二面角ECOB−−的平面角为,则为钝角,所以4433coscos,33116116mnmnmn=−=−=−=−++,所以二面角ECOB−−的余弦值为4
3333−.··················································15分17.(15分)某小区有3000名居民,想通过验血的方法筛选乙肝病毒携带者,假设携带病毒的人占%a.为减轻工作量,随机地按n人一组分组,然后将各组n个人的血样
混合在一起化验.若混合血样呈阴性,说明这n个人全部阴性;若混合血样呈阳性,说明其中至少有一人的血样呈阳性,就需要对每个人再分别化验一次。(1)若0.2,20,an==试估算该小区化验的总次数;(2)若0.9a=,且每人单独化验一次花费10元,n人混合化验一次花费9n+元,求当n为何值时,
每个居民化验的平均费用最少.注:假设每位居民的化验结果呈阴性还是阳性相互独立.当00.01p时,(1)1npnp−−.【答案】(1)270;(2)10【解析】(1)设每组需要检验的次数为X,若混合血样为阴性,则X=1,若混合血样呈阳性,则X=21,1分zxyMABC
DOE学科网(北京)股份有限公司所以20(1)(10.002)PX==−,20(21)1(10.002)PX==−−,························3分所以202020()1(10.002)21[1(10.002)]2120(10.00
2)EX=−+−−=−−2120(1200.002)1.8−−=·······································································5分一共有3000201
50=组,故估计该小区化验的总次数是1.8150270=.··········7分(2)设每组n人总费用为Y元,若混合血样呈阴性,则Y=n+9;若混合血样呈阳性,则Y=11n+9,8分故(9)(10.009)nPYn=+=−,(119)1(10.009)nPYn=+=−−········
·············10分()(9)0.991(119)(10.991)11100.9919nnnEYnnnn=+++−=−+············12分每位居民的化验费用为()11100.99199911100.9911110(10.009)nn
EYnnnnnnn−+==−+−−+=9911100.09120.092.8nnnn−+++=元·······14分当且仅当90.09nn=,即10n=时取等号,故n=10时,每个居民化验的平均费用最少.15分18.(17分)在平面直角坐标系xOy
中,已知()1,1A,()1,1B−,动点P满足OPmOAnOB=+,且1mn=.设动点P形成的轨迹为曲线C.(1)求曲线C的方程;(2)过点()2,2T的直线l与曲线C交于M,N两点,试判断是否存在
直线l,使得A,B,M,N四点共圆.若存在,求出直线l的方程;若不存在,说明理由.【答案】(1)22144xy−=;(2)不存在【解析】(1)设(),Pxy,则(),OPxy=uuur,()1,1OA=,()1,1OB=−,·········
··········1分因为OPmOAnOB=+,所以()()()(),1,11,1,xymnmnmn=+−=+−,·················2分所以xmn=+,ymn=−,所以2xym+=,2xyn−=,····························
·······3分又因为122xyxymn+−==,整理得22144xy−=,···········································4分所以曲线C的方程为22144xy−=;················
···············································5分(2)易知当l的斜率不存在时,直线l与曲线C没有两个交点,所以直线l的斜率存在,6分设l:()22ykx=−+,将直线l与曲线C联立,得22(2)21
44ykxxy=−+−=,消去y,整理得()22212(22)4880kxkkxkk−−−−+−=,··································7分学科网(北京)股份有限公司因为()()22224(22)414883
2(1)0kkkkkk=−−−−+−=−且210k−,所以1k且1k−,·················································································8分
设()11,Mxy,()22,Nxy,则1241kxxk+=+,21224881kkxxk−+=−,所以MN的中点22,11kHkk++,且()222121212141xxkxMxxxkN=−+=+−+,9
分将1241kxxk+=+,21224881kkxxk−+=−代入上式,整理得()22142(1)(1)kkkMN+=+−,····························································10分当0k时,线段M
N的中垂线方程为1l:12214111kyxxkkkkk=−−+=−++++,11分令y=0,解得41kxk=+,即1l与x轴的交点坐标为4,01kQk+,·······················
·12分当k=0时,线段MN的中垂线为y轴,与x轴交于原点,符合Q点坐标,·········13分因为AB的中垂线为x轴,所以若A,B,M,N共圆,则圆心为4,01kQk+,所以2222224MNQAQMQHHMQH==+=+,················
························14分所以()2222281442211111(1)(1)kkkkkkkkk+−−+=++++++−,·······························15分整理得32622100kkk−++
=,即()22(1)3450kkk+−+=,······························16分因为1k且1k−,所以上述方程无解,即不存在直线l符合题意.········································
······17分19.(17分)在高等数学中,我们将()yfx=在0xx=处可以用一个多项式函数近似表示,具体形式为:()()()()()()()()()200000002!!nnfxfxfxfxfxxxxxxxn=+−+−++−+(其中()()nfx表示()fx
的n次导数*3,nnN),以上公式我们称为函数()fx在0xx=处的泰勒展开式.当00x=时泰勒展开式也称为麦克劳林公式.比如ex在0x=处的麦克劳林公式为:22111e12!3!xnxxxxn=+++++
+!,由此当0x时,可以非常容易得到不等式2231111,1,1,226xxxexexxexxx++++++请利用上述公式和所学知识完成下列问题:(1)写出sinx在0x=处的泰勒展开式.(2)若30,2x
,sine1axx+恒成立,求a的范围;(参考数据5ln0.92)学科网(北京)股份有限公司(3)估计5ln3的近似值(精确到0.001)【答案】(1)1352111(1)sin3!5!(21)!nnxxxxxn−−+−=−+++−;(2)1a
;(3)0.511【解析】(1)sinx在0x=处的泰勒展开式为:1352111(1)sin3!5!(21)!nnxxxxxn−−+−=−+++−,·············································2分(2)因为1352111(1)
sin3!5!(21)!nnxxxxxn−−+−=−+++−由sinx在0x=处的泰勒展开式,先证3310,,sin26xxxx−,令3211()sin,()cos1,()sin62fxxxxfxxxfxxx=−+=−+
=−,······················3分()1cosfxx=−,易知()0fx,所以()fx在30,2上单调递增,所以()(0)0fxf=,所以()fx在30,2上单调递增,所以()(0)0fxf=,
·····4分所以()fx在30,2上单调递增,所以()(0)0fxf=,再令31()ln(1)6gxxxx=−−+,30,2x,易得1(1)(2)2()1xxxgxx−−+=+,所以
()gx在(0,1)上单调递增,在31,2上单调递减,·······································6分而3155(0)0ln02162,gg==−,所以30,,()02xgx恒
成立,··················7分当1a时,31sinsinln(1)6axxxxx−+,所以sine1axx+成立,·············8分当1a时,令()sinln(1)hxaxx=−+,30,2x
,易求得(0)10ha=−,所以必存在一个区间(0,)m,使得()hx在(0,)m上单调递减,所以(0,)xm时,()(0)0hxh=,不符合题意.······································
······10分综上所述,1a.··················································································
····11分(3)因为1154lnln,1314+=−转化研究1ln1xx+−的结构···············································12分23456ln(1)23456xxxxxxx+=−+−+−+·····················
·····························13分23456ln(1)23456xxxxxxx−=−−−−−−−················································14
分两式相减得35122ln2135xxxxx+=+++−···················································15分学科网(北京)股份有限公司取1,4x=得35512121ln2()()0.5108343454=
+++所以估计5ln3的近似值为0.511(精确到0.001).·······································17分