数学三角函数化简题

问题描述:

数学三角函数化简题
2(sin 120)^2+(sin 30)^2

2(sin 120)^2+(sin 30)^2
=2(sin 60)^2+(sin 30)^2
=2(cos30)^2+(sin 30)^2
=2cos²30+sin²30
=cos²30+cos²30+sin²30
=cos²30+1
=(√3/2)²+1
=3/4+1=7/4