2(√6+√2)[sinA+sin(150-A)]
问题描述:
2(√6+√2)[sinA+sin(150-A)]
得
4(√6+√2)*sin75cos(A-75)
答
sinA+sinB=2sin[(A+B)/2]cos[(A-B)/2]
2(√6+√2)[sinA+sin(150-A)]
得
4(√6+√2)*sin75cos(A-75)
sinA+sinB=2sin[(A+B)/2]cos[(A-B)/2]