sin(α+3π⼀2)等于什么?

2025-12-13 22:35:56
推荐回答(1个)
回答1:

sin(3π/2+α)

=sin(π+ π/2+α)
= - sin(π/2+α)
= - cosa
或者 套用公式
sin(3π/2+α)=sin(3π/2)cosa+cos(3π/2)sina= -cosa