arc sin(-1/2)=?
问题描述：
arc sin(-1/2)=?
答
-30
答
-π/6+2kπ
答
-30°+2kπ
答
-30+K*360
k属于Z
答
arc sin(-1/2)=-π/6
因为arc sinx范围就是〔-π/2,π/2〕