y=2√3 sinxcosx-2sin^2x的单调区间
问题描述:
y=2√3 sinxcosx-2sin^2x的单调区间
答
y=2√3sinxcosx-2sin²x
=√3sin2x+cos2x-1
=2(√3/2sin2x+1/2cos2x)-1
=2sin(2x+Л/6)-1
当2x+π/6∈(2kπ-π/2,2kπ+π/2)时,原函数单调递增,x∈(kπ-π/3,kπ+π/6)
同理x∈(kπ+π/6,kπ+2π/3)时,原函数单调递减
答
y=2√3 sinxcosx-2sin^2x
=√3 sin2x-1+cos2x
=2(√3/2 sin2x+1/2cos2x)-1
=2sin(2x+π/6)-1
x在[kπ-π/3,kπ+π/6]单调递增
x在[kπ+π/6,kπ+4π/3]单调递减