(共32张PPT)
2025年4月
东三省精准教学
联考 数学
1.已知在复平面内对应的点为(-1,2),则在复平面内对应的点为
A.(-2,-1) B.(-1,-2) C.(2,1) D.(1,2)
1.【答案】A
【解析】易知 ,则 ,所以 在复平面内对应的点为 .
故选:A.
2.已知命题p: ∈(0,+∞),>>;命题q: ∈(0,+∞),=ln x,则
A.p和q都是真命题 B. p和q都是真命题
C.p和 q都是真命题 D. p和 q都是真命题
2.【答案】D
【解析】对于命题 ,当 时, ,所以 为假命题;
对于命题 ,因为 , 成立,所以为 假命题.
故选:D.
3.已知为等差数列的前n项和,若,且=1,则=
A.2 025 B.-2 025 C.1 D.-1
3.【答案】B
【解析】∵ ,∴ ,∴ ,又 ,∴ ,
∴ .
故选:B.
4.某学校为了拓展学生的国际视野,培养学生的创新精神,让学生学有动力,学有信心,举办了英语手抄报比赛.为了解考生的成绩情况,抽取了样本容量为n的部分考生成绩,得到如图所示的频率分布直方图,则估计考生成绩的第70百分位数为
A.74 B.75 C.76 D.77
4.【答案】C
【解析】由频率分布直方图可知,考生成绩的第70百分位数为 .
故选:C.
5.已知函数f(x)=sin(ωx+φ)(ω>0,0<φ<π)的最小正周期为π,若将f(x)的图象向右平移个单位长度后所得的图象与曲线y=f(x)关于x=对称,则φ=
A. B. C. D.
5.【答案】D
【解析】由题意知, ,得 ,则 .
由 ,即 ,
得 , ,解得 , ,∵ ,∴ .
故选:D.
6.已知椭圆的左、右焦点分别为过的直线与交于,两点,若,且∠,则的离心率为
A. B. C. D.
6.【答案】D
【解析】设 ,由 ,得 ,由椭圆定义可知 , ,
∵ ,∴在 中,由余弦定理得 ,解得 或
(舍去),∴在 中, , , ,
∴ ,解得 ,∴离心率 .
故选:D.
7.记函数 的零点分别为,则
A. B.=1 C. D.
7.【答案】B
【解析】∵函数 , 的零点分别为 ,∴ , ,
由 ,得 ,∴ ,即 ,
显然函数 在R上单调递增,∴ ,∴ ,即 .
故选:B.
8.设函数,若,则的最小值为
A. B.e C. D.e
8.【答案】A
【解析】令 , ,则 ,
当 时, ;当 时, ;
当 时, ;当 时, .
由 ,知 ,所以 , .
令 ,则 ,
当 时, , 单调递减;当 时, , 单调递增,
所以 ,故 的最小值为 .
故选:A.
9.下列正方体的平面展开图中,满足在该正方体中的是
A. B. C. D.
9.【答案】AC
【解析】将正方体的平面展开图还原成立体图,易知A,C选项中 ,
B选项中直线与所成的角为,D选项中直线与所成的角为.
故选:AC.
10.设双曲线=1的左、右焦点分别为,且.为上关于原点中心对称的两点,则
A.的实轴长为 B.
C.若 ,则直线的斜率为 D.若=,则
10.【答案】ABD
【解析】设为的半焦距,则 ,由 ,得 ,所以的实轴长 为 ,故A正确;由于 关于原点中心对称, 关于原点中心对称,所以 ,所以
,故B正确;设为坐标原点,由 ,解得 ,所以 ,
所以直线的斜率为 ,故C错误;由 , ,可得 , ,且 ,所以 ,又 ,所以 ,故D正确. 故选:ABD.
11.设函数,若,且,则
A.实数的取值范围为[1,+∞) B. ∈(0,+∞),≥
C. D.当时,
11.【答案】BCD
【解析】对于A选项,∵ ,∴当 时, , 单调递增,
∴ ,且 不可能成立;
当 时, 在区间 和 上单调递增,在区间 上单调递减,
由 的图象可知,符合题设条件 ,且 ,
∴实数的取值范围为 ,故A错误;
对于B选项,由A选项分析可知 ,
故当 时, ,故B正确;
【解析】对于C选项,∵ ,∴ , ,∴ .由 ,得 ,∴ ,
∵ ,∴ ,即 ,
由基本不等式可知 (当且仅当 时取等号),∴ ,
∴ ,∴ ,故C正确;
对于D选项,由C选项分析可知 ,且 ,
∵ ,∴ ,∴ ,即 ,∵ ,∴ ∴ ,
令函数 ,则 ,∵ ,∴易知 的最小值为 ,即 ,∴ ,即 ,故D正确.故选:BCD.
12.在菱形中,为边的中点,若 ,则 .
12.【答案】
【解析】方法一: ,
∵ ,且由对称性易知 ,
∴ .
方法二:设 , 在 上的投影向量分别为,易知 ,
由数量积的几何意义可知, ,∴ .
故答案为: .
13.已知tan(α+β)=,tan(α-β)=,且β为钝角,则β= .
13.【答案】
【解析】 ,
∵为钝角,∴ ,∴ ,又 ,∴ ,∴ .
故答案为:.
14.已知数列满足,且对任意,有递推关系式: ,
定义数列为 ,则.
14.【答案】496
【解析】已知 ,①
当 时, .②
用①式减去②式可得 ,
即
当 时, 所以 是以 为首项,1为公差的等差数列,
则 即 (为偶数);
当 时, 所以 是以 为首项,5为公差的等差数列,
则 即 (为奇数).
因为 ,所以
故答案为:496.
15.【答案】(1) (6分) (2)2(7分)
【解析】(1)在 中,由正弦定理 ,得 ,
由已知 ,得 ,···································································1分
即 ,···············································································2分
∴ ,·····································································································3分
∵在 中, ,∴ , ∴ ,
∴ ,·············································································································4分
15.(13分)记的内角的对边分别为,已知 .
(1) 求;
(2)若为边的中点,且满足∠= ,求.
又 ,∴ ,∴ ,······································································5分
又 ,∴ .·········································································································6分
(2)∵为中点,且 , ,
∴ ,················································································7分
设 ,记 ,则 ,
又 ,·························································································9分
∴在 中,由正弦定理,得 ,即 ,·················10分
即 ,
∴ ,即 ,······································································12分
∴ ,即 .···························································································13分
16.(15分)已知函数,,其中,∈R.
(1)若曲线在点处的切线与直线垂直,且,求,的值;
(2)若函数在区间(0,+∞)上存在极大值,求的取值范围.
16.【答案】(1) (6分) (2)的取值范围是 (9分)
【解析】(1)因为 ,
所以 ,····························································2分
所以 ,依题意, ,得 .····························································4分
又 , ,且 ,所以 .
所以 .·····························································································································6分
(2)由题意, ,所以 ,·····················7分
令 ,
则 ,······································································8分
令 ,则 ,解得 或 .······················································9分
当 时, ,所以 在 上单调递增;···············································10分
当 时, ,所以 在 上单调递减;················································11分
当 时, ,所以 在 上单调递增.··························································12分
则 在 处取得极大值 ,····················································································13分
在 处取得极小值 .···························································································14分
因为 在区间 上存在极大值,所以 与 的图象在 上有交点,
且在交点左侧 的导数大于0,右侧导数小于0,
所以的取值范围是 .·······································································································15分
17.(15分)如图,在多面体中,是边长为2的等边三角形,⊥平面, , ,,.
(1)记为的中点,证明:⊥平面;
(2)设为棱上的动点,求直线与平面所成角的正弦值的最大值.
17.【答案】(1)证明见解析(6分) (2) (9分)
【解析】(1)证明:如图,取 中点,连接,.
在直角梯形 中, , ;在等边三角形 中, .
∵ , ,∴ , ,∴四边形 是平行四边形,············2分
∴ .···························································································································3分
∵ 平面 ,又 平面 , ,又 , , 平面 , 平面 ,
∴ 平面 ,··············································································································5分
∴ 平面 .········································································································6分
(2)如图,以为坐标原点,建立空间直角坐标系,
则 , , , ,···························································7分
则 , ,·········································································8分
设 ,则 ,则 ,···················9分
设 为平面 的一个法向量,
则 即 令 ,则 , ,得 ,··············11分
设直线 与平面 所成的角为 ,
则 ,
当且仅当 时,取等号. ············································································································14分
故直线 与平面 所成角的正弦值的最大值为 .····················································15分
18.(17分)有一摸球游戏如下:盒子中有红、黄、绿三种颜色的球各3个,球除颜色外其他均相同,两人摸球,规定每人一次从盒中摸3个球,第二人从第一人摸球后剩余的6个球中再摸3个球.记每个人摸到的3个球中颜色相同的球的最大数量为其得分,规定得分高者获胜.现有甲、乙二人参与此摸球游戏,记甲、乙的得分分别为X,Y.
(1)若甲先摸球,求X,Y 的分布列及其数学期望;
(2)在甲先摸球的情况下,分别计算甲获胜的概率和乙获胜的概率,并判断参赛者获胜的概率是否受摸球先后顺序的影响.
18.【答案】(1)答案见解析(12分) (2)答案见解析(5分)
【解析】(1)在甲先摸球的情况下,记甲摸到的三种颜色的球的数量由多到少分别为,, ,
则 , ,且 可能的取值有 , , ,···················1分
则 ,··································································································2分
,·······································································································3分
,····································································································4分
故的分布列为
.··························································································5分
在甲先摸球的情况下,记乙摸到的三种颜色的球的数量由多到少分别为,, ,
则 , ,且 可能的取值有 , , ,
则
·············································································7分
··············· 9分
················································································11分
故的分布列为
.··············································································································12分
(2)在甲先摸球的情况下,由题意,
···························································································································14分
·························································································································16分
则 ,即先摸球和后摸球获胜的概率一样,
故参赛者获胜的概率不受摸球先后顺序的影响.·····················································································17分
19.(17分)已知经过定点的动圆与直线相切,记圆心的轨迹为曲线,直线与曲线交于不同的两点,,以
分别为切点作曲线的切线,,与的交点为.
(1)求点的轨迹方程;
(2)设点,连接,,分别与曲线的另一个交点为,,直线与轴相交于,连接
,分别与曲线的另一个交点为,直线与轴相交于,…,连接,分别与曲线的另一个交点为,直线与轴相交于,已知.
(ⅰ)求数列的通项;
(ⅱ)已知,, 为数列的前项和,求使不等式成立时,的最小值.
19.【答案】(1) (5分) (2)(i) (7分) (ii)的最小值为9(5分)
(1)依题意可知,动圆的圆心到点 与到直线 的距离相等,根据抛物线定义可得曲线 是以 为焦点, 为准线的抛物线,
所以曲线 的方程为 ,····························································································2分
则直线: 经过抛物线的焦点,
设 , ,
联立 整理得 恒成立,则
又 可化为 ,则 ,···············································································3分
所以 , ,联立 ,
消可得 ,····················································4分
又因为,所以点的轨迹方程为 .····················································································5分
(2)(i)设 ,则 , ,又 , ,
则 ,又 ,所以 ,
即直线 的方程为 ,········································································6分
整理得 ,令 ,可得 ,①
同理可得 的方程为 ,令 ,可得 ,②··············7分
又直线 的斜率为 ,
所以直线 的方程为 ,·······································································8分
令 ,得 ,
由(1)可知, ,
①×②可得 .
于是可得 ,即 ,又因为 ,则 ,··············································9分
于是 ,即 ,即 ,
即 ,又 ,
所以数列 是以为1首项,2为公比的等比数列,························································11分
则 ,所以 ,所以 .·························································12分
(ii)由(i)可知, , ,则 ,···························13分
所以 ,
则 ,
两式作差可得 .
所以 .········································································································15分
令 ,即 .
当 时,显然不合题意;
当 时, 随着的增大而增大,
又 ,
,
,
则满足不等式 的的最小值为9.········································································17分
谢谢聆听
联考 数学高三数学
7.记函数f(x)=e+x,g(x)=n(-x)+的零点分别为a,b,则
本试卷满分150分,考试时间120分钟
A.
B.ab=1
C.ab=2
D.abze
e
注意事项:
8.设函数f(x)=(x-a)(lnx-b),若f(x)≥0,则ab的最小值为
1.答卷前,考生务必将自己的姓名、准考证号填写在答题卡上。
B.-e
D.e
2.回答选择题时,选出每小题答案后,用铅笔把答题卡上对应题目的答案标号涂黑。如需改动,用橡皮擦干净
c
后,再选涂其他答案标号。回答非选择题时,将答案写在答题卡上,写在本试卷上无效。
二、选择题:本题共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
3.考试结束后,将本试卷和答题卡一并交回。
分,部分选对的得部分分,有选错的得0分
9.下列正方体的平面展开图中,满足在该正方体中AB⊥CD的是
一、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,只有一项是符合题目要求的,
B
d Bc
A.P
B.
1.已知z在复平面内对应的点为(-1,2),则z在复平面内对应的点为
C.
D.
D
A.(-2,-1)
B.(-1,-2)
C.(2,1)
D.(1,2)
2已知命题p:Ye(0,+m),命题g:3xe(0,+m).e=n,则
10.设双曲线C:行21(a>0)的左、右焦点分别为F,F,且1FB,1=4A,B为C上关于原点中心对称的两
点,则
A.p和q都是真命题
B.p和g都是真命题
A.C的实轴长为22
B.IIAF,I-IBF,II=2√2
细
C.p和g都是真命题
D.p和g都是真命题
C若S,=4,则直线B的斜率为
IFAI 1
3.已知Sn为等差数列{an}的前n项和,若S0s=S08,且a2=1,则S2s三
D.若FA3则B上FFB,
A.2025
B.-2025
C.1
D.-
11.设函数fx)=x3-3ax+a3,若fx1)=f(x2)=f(x3)=t,且x14.某学校为了拓展学生的国际视野,培养学生的创新精神,让学生学有动力,学有信心,举办了英语手抄报比赛.为
A.实数a的取值范围为[1,+)
了解考生的成绩情况,抽取了样本容量为的部分考生成绩,得到如图所示的频率分布直方图,则估计考生成绩
B.Hxe(0,+∞),fx)≥-1
的第70百分位数为
C.2,a组距
D.当2x2=x,+x;时,1≥3lna+1
0.04
.30
三、填空题:本题共3小题,每小题5分,共15分.
12.在菱形ABCD中,E为边AD的中点,若AB·AC=2,则BE·AC=
0M0090100从统分
13.已知tan(a+B)=2-3,tan(a-B)=2+3,且B为钝角,则B=
蜜
14.已知数列{an}满足a1=1,且对任意n≥1,有递推关系式:a+1+an=3n+(-1)",
A.74
B.75
C.76
D.77
定义数列{bn}为bn=an·an+1,则b1o-bs=
5.已知函数x)=sim(a+p)(ω>0,0<9四、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
图象与曲线y=(x)关于x=2对称,则9=
15.(13分)记△MBC的内角A,BC的对边分别为a,66,已知2a+,06-=0,
c cosC
c
D S7
(1)求C;
6
6
(2)若D为边AB的中点,且满足∠ACD=牙,求am∠ADC,
6已知椭圆c:若+
:。+方=1(>0)的左,右焦点分别为F,P,过F,的直线与C交于A,B两点,若1AF,1=3引BF,1,
且∠F,AB=牙,则C的离心率为
摇
马
数学第1页(共4页)
数学第2页(共4页)】