Question

函数f（x）=sinxcosx的单调递增区间是什么呢？

过程具体一点哦~

Answer 1

f(x)=sinxcosx=1/2*sin2x
sin2x递增则2kπ-π/2<2x<2kπ+π/2
kπ-π/4<x<kπ+π/4
所以增区间是(kπ-π/4，kπ+π/4)

Answer 2

f（x）=sinxcosx
=1/2sin2x
-π/2<2x<π/2
-π/4<x<π/4
单调递增区间是(-π/4,π/4)