早教吧作业答案频道 -->数学-->
cso15°cos30°+cos105°sin30°的值是()A.22B.32C.12D.1
题目详情
cso15°cos30°+cos105°sin30°的值是( )
|
A.
| B.
| C.
| D.1 |
A.
| B.
| C.
| D.1 |
A.
| B.
| C.
| D.1 |
A.
| B.
| C.
| D.1 |
A.
| B.
| C.
| D.1 |
| ||
2 |
| ||
2 |
1 |
2 |
| ||
2 |
| ||
2 |
1 |
2 |
| ||
2 |
| ||
2 |
| ||
2 |
2 |
2 |
2 |
2 |
| ||
2 |
| ||
2 |
| ||
2 |
3 |
3 |
3 |
3 |
1 |
2 |
1 |
2 |
1 |
2 |
▼优质解答
答案和解析
cos15°cos30°+cos105°sin30°
=cos15°cos30°+cos(90°+15°)sin30°
=cos15°cos30°-sin15°sin30°
=cos45°
=
.
故选A cos15°cos30°+cos105°sin30°
=cos15°cos30°+cos(90°+15°)sin30°
=cos15°cos30°-sin15°sin30°
=cos45°
=
.
故选A cos15°cos30°+cos105°sin30°
=cos15°cos30°+cos(90°+15°)sin30°
=cos15°cos30°-sin15°sin30°
=cos45°
=
.
故选A cos15°cos30°+cos105°sin30°
=cos15°cos30°+cos(90°+15°)sin30°
=cos15°cos30°-sin15°sin30°
=cos45°
=
.
故选A
2
2 2 2 2 2 2 2 .
故选A
cos15°cos30°+cos105°sin30° =cos15°cos30°+cos(90°+15°)sin30° =cos15°cos30°-sin15°sin30° =cos45° =
故选A |
=cos15°cos30°+cos(90°+15°)sin30°
=cos15°cos30°-sin15°sin30°
=cos45°
=
| ||
2 |
故选A
=cos15°cos30°+cos(90°+15°)sin30°
=cos15°cos30°-sin15°sin30°
=cos45°
=
| ||
2 |
故选A
=cos15°cos30°+cos(90°+15°)sin30°
=cos15°cos30°-sin15°sin30°
=cos45°
=
| ||
2 |
故选A
=cos15°cos30°+cos(90°+15°)sin30°
=cos15°cos30°-sin15°sin30°
=cos45°
=
| ||
2 |
故选A
| ||
2 |
2 |
2 |
2 |
2 |
故选A
看了 cso15°cos30°+c...的网友还看了以下:
求一数列.高2.a(n+1)=2an/2an+1已知a1=1a(n+1)=2an/2an+1求数列 2020-04-25 …
利用等比数列的前n项和的公式证明:如果a不等于b,且a,b都不为0,则a^n+a^(n-1)b+a 2020-05-13 …
利用等比数列的前n项和的公式证明a^n+a^(n+1)×b+a^(n-2)×b^2+…+b^n=〔 2020-05-13 …
已知数列a(n)为等比数列,a(4)=16,q=2,数列b(n)前N项和s(n)=1/2*n的平方 2020-05-13 …
15.6克苯溶于400g环己烷,该溶液的凝固点比纯溶剂低10.1℃.计算环己烷的凝固点降低常数.我 2020-05-16 …
如何推导这个因式分解题!a^n-b^n=(a-b)[a^(n-1)+a^(n-2)b+……+b^( 2020-05-16 …
A、B、C这3个小于10而相邻自然数,A*B*C=1+2+3……+24+25,其中,漏加N.已知A 2020-06-02 …
已知(a^n·b^m·b)^3=a^19·b^15,那么m、n的值分别是?3Q题中a^n指的是a的 2020-06-03 …
数列bn满足b1=3/4,且3bn-bn-1=n,求bn注:bn-1是b(n一1) 2020-06-06 …
"奔向"中的「奔」念bēn还是bèn 2020-07-01 …