cos(α+β)sin(α-β)+1/2sinαcosβ=0,3(sinα)^2+2(sinβ)^2=1,α、β属于（0,π/2)求sin(α+β)纠结好久了~

Question

cos(α+β)sin(α-β)+1/2sinαcosβ=0,3(sinα)^2+2(sinβ)^2=1,α、β属于（0,π/2) 求sin(α+β)纠结好久了~

Answer 1

比较难,只能教你一些思路.你要知道这个和差化积公式,sina-sinb=2【cos(a+b)/2】乘【sin(a-b)/2】所以这里cos(α+β)sin(α-β)可转化为sin2a-sin2b=2【cos(a+b)】乘【sin(a-b)】即cos(α+β)sin(α-β)=(sin2a-sin2b...