sin(-1200°)-cos1290°+cos(-120)°+cos(-1020)°-sin(-1050°)+tan855°

来源:学生作业帮助网 编辑:作业帮 时间:2024/04/29 03:06:20

sin(-1200°)-cos1290°+cos(-120)°+cos(-1020)°-sin(-1050°)+tan855°
sin(-1200°)-cos1290°+cos(-120)°+cos(-1020)°-sin(-1050°)+tan855°

sin(-1200°)-cos1290°+cos(-120)°+cos(-1020)°-sin(-1050°)+tan855°
sin(-1200°)=-sin(3*360° +120° )=-sin120°=-1/2
cos1290°=cos(4*360°-150°)=cos150°=-√3/2
cos(-120)°=cos120°=-1/2
cos(-1020)°=cos1020°=cos(3*360°-60°)=1/2
sin(-1050°)=sin(3*360°-30°)=-sin30°=-1/2
tan855°=tan135°=-1
sin(-1200°)-cos1290°+cos(-120)°+cos(-1020)°-sin(-1050°)+tan855°
=-1/2-(-√3/2)-1/2+1/2-(-1/2)+(-1)=(√3-2)/2