Question

210,240,270,310,330,度的各角正弦,余弦函数值

Answer 1

sin210°=sin(180°+30°)=-sin30°=-1/2

sin240°=sin(180°+60°)=-sin60°=-√3/2

sin270°=sin(180°+90°)=-sin90°=-1

sin300°=sin(360°-60°)=-sin60°=-√3/2

sin330°=sin(360°-30°)=-sin30°=-1/2

cos210°=cos(180°+30°)=-cos30°=-√3/2

cos240°=cos(180°+60°)=-cos60°=-1/2

cos270°=cos(180°+90°)=-cos90°=0

cos300°=cos(360°-60°)=cos60°=1/2

cos330°=cos(360°-30°)=cos30°=√3/2