1 . 判断正误(正确的写正确,错误的写错误)
(1)
是
的倍角,
是
的倍角.( )
(2)二倍角的正弦、余弦、正切公式的适用范围是任意角.( )
(3)存在角
,使得
成立.( )
(4)对于任意角
,总有
.( )
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e09f77f82af581e630a9d834de3bcf7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b65e802bb1713b07e70be75488282d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b65e802bb1713b07e70be75488282d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e08b574831233d2b3d1f5a9a48733f63.png)
(2)二倍角的正弦、余弦、正切公式的适用范围是任意角.
(3)存在角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/265b833d3996bc15fa4f5d6bba1cb86a.png)
(4)对于任意角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e09f1768c70617a578cdd9b2718983bc.png)
您最近一年使用:0次
解题方法
2 . 若
,
,则
.( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/969b106918cf44777d177a0538da8cb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5bec99b0f7da69dd2f6ef8e88c35b81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37fd8ea26779711eea4ffb700c6ec207.png)
您最近一年使用:0次
3 . 若
,
,则
恒成立.( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4f0158f5bead170477f11e35bd89ee3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/232d1ce3ad14256b1543e6007ff1675d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebbd299293ea948da9d68a27f8e5841e.png)
您最近一年使用:0次
4 . 存在某个角
,使
.( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/342c52436f5e76dbff46c9e358872e6c.png)
您最近一年使用:0次