机车女孩
幼苗
共回答了19个问题采纳率:89.5% 举报
y=sin
4x+2
3sinxcosx-cos
4x
=(sin
2x+cos
2x)(sin
2x-cos
2x)+
3sin2x
=
3sin2x-cos2x
=2sin(2x-[π/6]).
(如)该函数的最小正周期是π;
(2)列表:
2x-[π/6] 了 [π/2] π [3π/2] 2π
x [π/如2] [π/3] [7π/如2] [了π/6] [如3π/如2]
2sin(2x-[π/6]) 了 2 了 -2 了描点作八:
![](https://img.yulucn.com/upload/9/1c/91c77a5e8f29230bc1e9a6d7972c4949_thumb.jpg)
单调递增区间是[了,
π
3]和[
了π
6,π]
1年前
10