f(x)=-1+2根号3sinxcosx+2cos2x
=√3sin2x+cos2x
=2sin(2x+π/6)
1. 单增区间为2x+π/6∈[2kπ-π/2, 2kπ+π/2] x∈[kπ-π/3, kπ+π/6]
单减区间为2x+π/6∈[2kπ+π/2, 2kπ+3π/2] x∈[kπ+π/6, kπ+2π/3]
2. 若角α,β的终边不共线,且f(α)=f(β)
则α,β之间相差π
即α+β=2kπ+π
所以tan(α+β)=tan(2kπ+π)=tanπ=0
希望能帮到你,祝学习进步O(∩_∩)O
第一问