2020年高考数学三角函数选择题专项训练
1.已知︱coos θ︱=coos θ,︱tan θ︱=tan θ,则2θ在 ( ) (A )第二、四象限 (B )第一、三象限
(C )第一、四象限或终边在x 轴上 (D )第二、四象限或终边在x 轴上 2.设βα,都是第二象限的角,若βαsin sin >,则( ) (A )βαtan tan > (B )βαcot cot < (C )βαcos cos > (D )βαsec sec > 3.函数x x y sin -=在
[]ππ,2上的最大值是( )
(A )π (B )12-π
(C )123+π (D )2
2
23-
π
4.设32πα=
,则=-+-)tan()sin(12
52π
ααπ( )
(A )222- (B )222+ (C )232+ (D )232- 5.若角α的终边落在直线0=+y x 上,则
=+
--α
αα
αcos cos 1sin 1sin 22( )
(A )2 (B )-2
(C )1 (D )0
6.设α是第二象限的角,则1csc sec sin 2-??ααα化简结果是( ) (A )1 (B )α2
tan
(C )α2
cot (D )-1
7.集合M ={α︱2
2
sin <
α},N ={β︱2
2
cos >
β},则M 、N 的关系是( )
(A )M =N (B )M
N (C )N M ? (D )N M
8.已知5
7cos sin =
+θθ,且,1tan >θ则θcos =( )
(A )53 (B )54
(C )53± (D )5
4
±
9.函数)2sin(2
5π+
=x y 的图象的一条对称轴方程是( )
(A )2π-=x (B )4π
-=x
(C )8
π=
x (D )4
5π
=
x
10.给出下面四个函数,其中既是区间(0,)2π上的增函数又是以
π为周期的偶函数的函数是( )
(A )x y 2tan = (B )x y sin =
(C )y =cos2x (D )x y cos =
11.函数x x x f sin cos )(2
+=在[]4352,ππ∈
x 上的最大值是( )
(A )45 (B )22
1+
(C )2
2
1+
- (D )1
12.函数)2sin(4x y -=π的单调递增区间是( )
(A )[
])(,8
38Z k k k ∈+-π
πππ (B )[])(2,28783Z k k k ∈++ππππ (C )[
])(,8
78
3Z k k k ∈+
+
ππππ (D )[])(2,2838Z k k k ∈+-ππππ
13.把函数),0()sin(π?ω?ω<>+=K x y 的图象向左平移6π个单位,再将图象上所有点的横坐标伸长到原来的2倍(纵坐标不变)所得图象的解析式是x y sin =,则( )
(A )6,2π?ω=
= (B )3,2π?ω-==
(C )6
21,π?ω=
= (D )1221,π?ω-==
14.在△ABC 中,三边a 、b 、c 与面积S 的关系是S =)(22241c b a -+,
则角C 应为( )
(A )300 (B )450 (C )600 (D )900
15.若()πθ2,0∈,且,tan cot cos sin θθθθ<<<则θ的取值范围是( )
(A )()24,ππ (B )()ππ,43
(C )()234
5,ππ (D )()ππ
2,47 16.函数)sin()sin(44x x y -++=π
π是( )
(A )奇函数且最大值是2 (B )偶函数且最大值是2 (C )奇函数且最大值是2 (D )偶函数且最大值是2 17.若1)cos()cos()cos(=---A C C B B A 则△ABC 是( ) (A )直角三角形 (B )等腰直角三角形
(C )等边三角形 (D )顶角为1200的等腰三角形
18.若3
πβα=
-,则βαsin sin ?的最大值是( )
(A )41 (B )43
(C )21 (D )2
3
19.函数)cos()sin()(44x x x f -+=π
πω的最小正周期为π,则正实数ω的值是( ) (A )41 (B )21
(C )1或3 (D )2 20.函数x
x x
x y 2sin 2cos 2sin 2cos -+=
的最小正周期为( )
(A )4π (B )2π (C )π (D )2π
21.若0cos cos cos sin sin sin =++=++γβαγβα,( )
(A )21 (B )-21
(C )-1 (D )1
22.已知,cos 1sin 2x x +=则2tan x
的值为( ) (A )21 (B )21或不存在
(C )2或21 (D )不存在 23.若,02
παβ<
<<且,)sin(,)cos(13554
=-=+βαβα那么=α2cos ( )
(A )6563 (B )-6563
(C )6533 (D )6556或-6516
24.设,cos ,325m =<<θπθπ则2sin θ=( )
(A )-2
1m
+ (B )-
2
1m -
(C )
2
1m + (D )
2
1m -
25.设,,214cos 22,13cos 13sin 2
60200=
-=+=c b a 则a 、
b 、
c 的大小关系是( ) (A )b c a >> (B )a b c >>
(C )a c b >> (D )b a c >>
26.设,2sin ,sin 53
o <=θθ则=2tan θ( ) (A )-21 (B )21
(C )31 (D )3
27.若函数x a x x f 2cos 2sin )(+=的图象关于直线8π-=x 对称,则a 的值等于( ) (A )2 (B )-2 (C )1 (D )-1 28.函数x
x
y cos 2sin 3-=
的值域为( )
(A )[]1,1- (B )[]
3,3-
(C )[]1,3- (D )[]3,1-
29.已知6
πβα=
+,则α、β满足关系式0tan 3tan 2)tan (tan 3=+++βαβαa 则=αtan ( ) (A )
)1(3
3
a - (B ))1(3
3a +
(C ))1(3a - (D ))1(3a +
30.使函数)2cos(3)2sin(??+++=x x y 为奇函数,且在[]
4,0π上是减函数的?的一个值是( )
(A )3π (B )35π
(C )32π (D )34π
31.已知,tan a x =则
=++x
x x
x 3cos cos 33sin sin 3( )
(A ))3(221+a a (B ))32(21
+a a (C ))3(22+a a (D ))3(22
-a a
32.已知,sin sin ,cos cos 31
21-=-=-βαβα则=+)sin(βα( )
(A )135 (B )135
- (C )1312 (D )1312-
33.已知,1cos sin 4
4=+αα那么=+ααcos sin ( ) (A )21 (B )2
1
±
(C )1 (D )1± 34.a
b
=
θtan ()0≠a 是使a b a =+θθ2sin 2cos 成立的( ) (A )充分不必要条件 (B )必要不充分条件
(C )充要条件 (D )既不充分又不必要条件 35.=++0
0020250cos 20sin 50cos 20sin ( )
(A )21 (B )-21
(C )43 (D )-43
36.△ABC 中,B =600,则C A cos cos 的取值范围是( )
(A )[]41,0 (B )(]41
21,-
(C )[)21
41, (D )[)0,41-
37.=-+0
00063cos 24cos 84cos 2263sin ( ) (A )
2
2
(B )-
2
2
(C )21 (D )-21
38.若,3
2π=
+y x 则y x 22cos cos +的最大值为( )
(A )2 (B )21 (C )23 (D )2
3
39.若169
60
cos sin =
A A )(24π