求下列三角函数值: ①-17π/3 ②21π/4 ③-23π/6 ④1500°
问题描述:
求下列三角函数值: ①-17π/3 ②21π/4 ③-23π/6 ④1500°
答
-17π/3=-6π+π/3sin(-17π/3)=sin(-6π+π/3)=sin(π/3)=√3/2cos(-17π/3)=cos(π/3)=1/2tan(-17π/3)=tan(π/3)=√321π/4=6π-3π/4sin(21π/4)=sin(6π-3π/4)=-√2/2cos(21π/4)=cos(6π-3π/4)=-√2/2tan(21...