2024 年春期高中一年级期中质量评估数学试题
参考答案
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1.本解答给出了一种或几种解法供参考,如果考生的解法与本解答不同,可根据试题的主
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2.对于 18题、19题等解答题涉及向量的书写规范,若考生思路正确但书写向量没加箭头,
该大题扣 2分.
一、选择题
题号 1 2 3 4 5 6 7 8
答案 B D B A D C B C
二、选择题
题号 9 10 11 12
答案 BC AD AC ACD
三、填空题(本大题共 4小题,每小题 5分,共 20分)
3 7 1 2
13.[0, ) ( ,2 ] 14. y sin(6x )
4 4 2 3
15 3. 16 2 2.
3 3
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.【解析】
(1)因为点Q在单位圆上且0 x2 ( 5,所以2 )
2 1 x 2 5 ,得 .········2分
5 5
由三角函数定义知, sin 5 ,cos 2 5 ,·············································4分
5 5
2sin 5cos
故 12 .··········································································5分
3sin 2cos
(2)由题意: sin sin( 2 5 ) cos ,···············································7分
2 5
cos cos( ) sin 5 ,························································9分
2 5
故 P( 5 , 2 5 ) .····················································································10分
5 5
18.【解析】
1
(1)NC BC BN a BD ··································································3分
3
高一数学参考答案 第 1 页(共 4 页)
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1 a (AD AB) a 1 (a 2 1
b) a b ··························6分
3 3 3 3
(2)因为MC MB BC 1 b a ,······························································8分
2
2 1 2
且由(1)知 NC (a b),所以 NC MC,······································10分
3 2 3
所以 NC / /MC,又C为公共点, 所以M ,N ,C三点共线. ·······························12分
19.【解析】
(1)设D点坐标为 (x, y),则 AB (1, 2), AD (x 1, y),·······························2分
x 1 2y 5 x 2 x 2
2 2 ,解得 或 ,···········································5分
(x 1) y 10 y 1 y 3
即点D的坐标为 (2,1)或 ( 2,3) ··································································6分
(2)由向量 c与a+b共线,令 c t(a b),t R,则b c ta (1 t)b,··················7分
r r 1
而向量 a,b 为单位向量,且 a b ,2
2 2 2
于是得 b c ta (1 t)b ta 2t(1 t)a b (1 t)2b t2 t 1 ·············8分
(t 1 3 3 )2 ,·············································································10分
2 4 2
1
(当且仅当 t 时取“=”) ········································································11分
2
所以 | b c | 3的最小值为 .······································································12分
2
20.【解析】
2 2 2
(1)(方法一:)由余弦定理得: cos B a c b ,又由题知: 2c cos B 2a b,···1分
2ac
a2 2 2
所以 2c ( c b ) 2a b,化简得 a2 b2 c2 ab,·································3分
2ac
2
cosC a b
2 c2 1
所以: ,·································································5分
2ab 2
π
因为C (0,
π ),故C .··········································································6分
2 3
(方法二:)由正弦定理得: 2sinC cos B 2sin A sin B,·································1分
sin B 2sin(B C) 2sinC cos B
sin B 2sin B cosC ··································· ··············································3分
高一数学参考答案 第 2 页(共 4 页)
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因为 sin B 0
1
所以: cosC ,··················································································5分
2
C π
π
因为 (0, ),故C .··········································································6分
2 3
(2)由余弦定理: c2 a2 b2 2ab cosC,
整理得 a2 5a 6 0,解得 a 2或 a 3 .····················································8分
当 a 2时, a2 c2 b2,最大角 B是钝角, ABC为钝角三角形,舍去;··········9分
当 a 3时, a2 c2 b2,最大角 B是锐角, ABC为锐角三角形,符合题意. ·····10分
1 1
所以 S ABC absin C 5 3
3 15 3
.···············································12分△ 2 2 2 4
21.【解析】
5π 5π
(1) 由题对任意 x R ,都有 f (x) f ,故当 x 时, f (x)取得最大值. ·······1分
12 12
π
因为 f (x)
在 ,
5π π
是单调函数,且 f (x)的图象关于点 ,0 对称,
6 12 6
T 5π π π
所以 得T π,所以
2
2 ················································3分
4 12 6 4 T
f x x 5π 5π π又因为函数 在 时取得最大值,所以 2kπ,k Z,
12 6 2
π 2kπ,k Z π π即 .因为 2 ,所以
3 ,··········································5分3
所以: f (x) sin 2x
π
3 .·········································································6
分
π 2π
(2)因为 x 0,
π
,令 t 2x
π
,则 t ,
2 3 3 3
y sin t π 2π 在 , 内的图象如图所示,···················7分 3 3
由题函数 g(x)
π
f (x) m x 0, 在 有两个零点 x , x , 2 1 2
y sin t y m π 2π即 与 在 ,
内有两个交点 t1, t2 ,3 3 ······································9
分
3
数形结合可得: m 1, t1 t2 2x
π π 5π
1 2x2 π,即 x1 x2 3 3 2
,······11分
6
f x x 5π π π π 3所以 1 2 sin
sin π
sin .····························12分
3 3 3 3 2
22.【解析】
(1) S = 1 S = 1 (1 1 3 3由题可知: CGD ACD S ABC )= =
3 ,·························2分
3 3 2 6 2 4
1
即 CG GD sin 60 = 3,所以GD=1,·················································3分
2 4
从而 GCD为等边三角形,则 BDG 120 , BD CD 1 ,························4分
高一数学参考答案 第 3 页(共 4 页)
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因为G为 ABC的重心,所以G为线段 AD的三等分点,所以 AD 3
在 ABD中,由余弦定理得: AB2 AD2 BD2 2AD BD cos BDG
32 12 2 3 1 cos120 13 ,··························································5分
所以 AB 13 .··················································································6分
(2)(方法一:) 由GB GC ,且D为 BC中点,则BD CD GD ,
不妨设 BD CD GD x ,则 AD 3x,BC 2x ,····································7分
在 ABC中, 由余弦定理: (2x)2 b2 c2 2bc cos BAC① , ··························8分
2 2 2 2 2 2
又因为 ADB ADC x (3x) c x (3x) b ,易得: 0② ·········9分
2 x (3x) 2 x (3x)
由①②解得:
2 2
cos BAC 2 (b c ) 2 b c 4 ( ) , (当且仅当b c时取“=”) ····················11分
5 bc 5 c b 5
4
故 cos BAC 的最小值为 .································································12分
5
2 2 1 2 1
(方法二:) GB AB AG AB AD AB (AB AC) AB AC ,
3 3 2 3 3
同理:GC 2 AC 1 AB ,··································································8分
3 3
由GB GC,得GB GC 0 ,
2 1
即GB GC ( AB AC) (2 AC 1 AB)
3 3 3 3
5 2AB AC 2 AB 2
2
AC 0 5,即 bc cos BAC 2 c 2 2 b 2,····················10分
9 9 9 9 9 9
2 2
cos BAC 2b 2c 2 b c 4 b c 4 ( ) ,当且仅当b c时,取“=”·····11分
5bc 5 c b 5 c b 5
4
故 cos BAC 的最小值为 .··········································································12分
5
高一数学参考答案 第 4 页(共 4 页)
{#{QQABQYAAggAAAJJAABgCEQEiCgEQkBEAACoOBEAIIAAASQFABCA=}#}2024年春期高中一年级期中质量评估
7.若a,B,0∈(0,罗),且cosa=tana,cosB=B,cos0-sin0,则a,A,0的大小是
数学
试题
A.aB
B.a<<0
C.B
D.B<0<
注意事项:
8.已知f(x)=sin(x十p),其中w>0,01.本试卷分第I卷(选择题)和第Ⅱ卷(非选择题)两部分,考生做题时将答案答在答题
象如下图,则f(答)=
卡的指定位置上,在本试卷上答题无效.
2.答题前,考生务必先将自己的姓名、准考证号填写在答题卡上。
A.-1
3.选择题答案使用2B铅笔填涂,非选择题答案使用0.5毫米的黑色中性(签字)笔或碳
素笔书写,字体工整,笔迹清楚
吗
4,请按照题号在各题的答题区域(黑色线框)内作答,超出答题区城书写的答案无效
5.保持卷面清洁,不折叠、不破损
c.2
第I卷选择题(共60分)
n-号
毁
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
二、多选题(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
符合题目要求的.)
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.)
戴
1.与角一2024°4'终边相同的角是
9.下列等式恒成立的是
A.-4044
B.-2244
C.31556
D.67556'
A.sin(ta)=sina
B.cos(a-)=sina
2.已知A(1,2),B(4,3),C(x,6),若AB∥AC,则x=
A.10
B.11
C.12
D.13
Csin(-受+e)=coa
D.tan(π+a)=-tang
3.在扇形AOB中,∠AOB=2,弦AB=2,则扇形AOB的面积是
10.已知向量a=(1,2),b1=2,a+b1=√7,则
A动
1
B.(sin1)
C.sin1
D.(sin1)2
4.在梯形ABCD中,∠BAD-∠CDA=90°,AD=5,则AD·BC
Aa在b上的投影数量是一己
BB在a上的授影向量是(-得,-5)
5
A.25
B.15
C.10
D.5
C.a与b夹角的正弦值是25
5
D.(4a+b)⊥b
5.在△ABC与△AB,C中,已知AB=AB=x,BC=B,C=3,∠C=∠C=5,若
△ABC≌△AB,C1,则
11.设函数f(x)=Asin(az十p)(其中A>0,w>0,-一元<9<0).若f(x)在[晋,受]上具有单
A.xE0,2]
B.x∈(0W3)
调性,且f(受)=管)=-f(答)=瓦,则
C.x∈[V3,十∞)
D.x[,+∞)U(2)
A.A=2
Ba-号
6,小娟,小明两个人共提一桶水匀速前进,已知水和水桶总重力为亡,两
人手臂上的拉力分别为,,且1=|1,与的夹角为0,下
Cp=-受
D当xe[-晋,]时)∈[-2w2
列结论中正确的是
12.在△ABC中,AB=2,AC=3,∠BAC=60°,则
.0越小越费力,0越大越省力
B始终有1=1-阿
A,△ABC的周长是5十√7
BBC边上的中线长
C.当9=时,1=
D.当0=罗时,1=G创
C.BC边上的角平分线长6
5
D.BC边上的高长3y
7
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