高一数学同步测试(3)—正、余弦的诱导公式
YCY 说明:本试卷分第Ⅰ卷和第Ⅱ卷两部分.第Ⅰ卷60分,第Ⅱ卷90分,共150分,答题时间120分钟.
第Ⅰ卷(选择题,共60分)
一、选择题(每小题5分,共60分,请将所选答案填在括号内) 1.下列不等式中,不成立的是
( A.sin130°>sin140° B.cos130°>cos140° C.tan130°>tan140° D.cot130°>cot 140°
2.sin(-
103π)的值等于 ( A.
1B.-
132 2 C.
2 D.-
32 3.已知函数f(x)?asinx?btanx?1,满足f(5)?7.则f(?5)的值为 (
A.5
B.-5
C.6
D.-6
4.sin
4?3·cos25?6·tan5?4的值是 ( A.-34 B.34
C.-
34 D.
34 5.在△ABC中,若sin(A?B?C)?sin(A?B?C),则△ABC必是 ( A.等腰三角形
B.直角三角形
C.等腰或直角三角形
D.等腰直角三角
6.1?2sin(??2)cos(??2)等于
( A.sin2-cos2
B.cos2-sin2
C.±(sin2-cos2) D.sin2+cos2
7.已知cos(75°+α)=13,α为第三象限角,则cos(15°-α)+sin(α-15°)的值为( A.-13
B.-
2221?223 C.-
1?23 D.
3
)
) ) ) ) ) )
8.若M={α|α=
k??-,k∈Z},N={α|-π<α<π=,则M∩N等于 25?3?7?4?A.{-,} B.{-} ,510105?3?4?7?3?7?C.{-,} D.{ } ,,?,?1010510510①sin(A+B)=sinC ②cos(A+B)=-cosC ③tan(A+B)=-tanC(C≠A.1个
?B?CA) ④sin=cos 222( )
9.已知A、B、C是△ABC的内角,下列不等式正确的有 ( )
B.2个 C.3个 D.4个
( )
D. D.
10.sin2150°+sin2135°+2sin210°+cos2225°的值是
A.
1 4B.
3 4C.
11 49 4( )
11.设tan1234??a,那么sin(?206?)?cos(?206?)的值为
A.
1?a1?a2 B.-
1?a1?a?22 C.
a?11?a?22
1?a1?a2
12.设α是第二象限角,且|cos
A.第一象限角
|=-cos
?2,则是
D.第四象限角
( )
B.第二象限角 C.第三象限角
第Ⅱ卷(非选择题,共90分)
二、填空题(每小题4分,共16分,请将答案填在横线上) 13.已知cos(75°+α)=
1,其中α为第三象限角,cos(118°-α)+sin(α-118°)= . 314.tan2018°的值为 15.若
1?tan?(sin??cos?)?1?3?22,则? .
1?tan?cot??sin??cos?cos(??4?)cos2(???)sin2(??3?)16.化简:=______ ___.
sin(??4?)sin(5???)cos2(????)三、解答题(本大题共74分,17—21题每题12分,22题14分) 17.求cos(-2640°)+sin1665°的值.
18.已知sin(3π+θ)=
值.
19.求证:cos(kπ±α)=(-1)kcosα(k∈Z).
20.已知f(tanx)?cot3x?cos3x,
cos(???)cos(??2?)1,求的?cos?[cos(???)?1]cos(??2?)cos(???)?cos(??)4 (1)求f(cotx)的表达式; (2)求f(?
3)的值. 3
21.化简:
1?2sin290?cos430?.
sin250??cos790?
22.若k∈Z,求证:
sin(k???)cos(k???)=-1.
sin[(k?1)???]cos[(k?1)???]
高一数学同步测试(3)参考答案
一、选择题
1.C 2.D3.B 4.A5.C 6.A7.B8.C9.D10.A11.B12.C 二、填空题 13. ?1?233 14. 15.1 16.-cosθ 33三、解答题
17.解析:
cos(-2640°)+sin1665°
=cos[240°+(-8)×360°]+sin(225°+4×360°)=cos240°+sin225°
=cos(180°+60°)+sin(180°+45°)=-cos60°-sin45°=-18.解析: sin(3π+θ)=-sinθ, ∴sinθ=-
1?2 21 4原式=
?cos?cos?11?= ?cos?(?cos??1)cos?(?cos?)?cos?1?cos?1?cos?22?=32 221?cos?sin?19.证明:当k=2n(n∈Z)时,
cos(kπ±α)=cos(2nπ±α)=cosα,此时(-1)k=1. 当k=2n+1(n∈Z)时,
cos(kπ±α)=cos(2nπ+π±α)=cos(π±α)=-cosα, 此时(-1)k=-1,
∴cos(kπ±α)=(-1)kcosα.
=
20.解析:(1)?f(tanx)?cot3x?cos3x, ?f(cotx)?f(tan(?2?x)?tan3x?sin3x.
(2)f(?3???)?f[tan(?)]?cot(?)?cos(?)?0. 36221?2sin(?70??360?)cos(70??360?)sin(180??70?)?cos(70??2?360?)
21.解析:原式=
(sin70??cos70?)21?2sin70?cos70?sin70??cos70?===-1 ?cos70??sin70?cos70??sin70?cos70??sin70?
22.证明:【法一】 若k为偶数,则
左端=
sin(??)cos??sin?cos?=-1, ?sin(???)cos(???)(?sin?)(?cos?)若k为奇数,则 左端=
sin(???)cos(???)sin?(?cos?)=-1 ?sin?cos(??)sin?cos?【法二】:可利用(kπ-α)+(kπ+α)=2kπ,[(k+1)π+α]+[(k+1)π
-α]=2(k+1)π进行证明. 左端=
sin(k???)cos(k???)sin(k???)cos(k???)==-1
?sin[(k?1)???]cos[(k?1)???]sin(???)[?cos(k???)]
22.证明:【法一】 若k为偶数,则
左端=
sin(??)cos??sin?cos?=-1, ?sin(???)cos(???)(?sin?)(?cos?)若k为奇数,则 左端=
sin(???)cos(???)sin?(?cos?)=-1 ?sin?cos(??)sin?cos?【法二】:可利用(kπ-α)+(kπ+α)=2kπ,[(k+1)π+α]+[(k+1)π
-α]=2(k+1)π进行证明. 左端=
sin(k???)cos(k???)sin(k???)cos(k???)==-1
?sin[(k?1)???]cos[(k?1)???]sin(???)[?cos(k???)]