计算:sin315°-sin(-480°)+cos(-330°)

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计算:sin315°-sin(-480°)+cos(-330°)计算:sin315°-sin(-480°)+cos(-330°)计算:sin315°-sin(-480°)+cos(-330°)原式=s

计算:sin315°-sin(-480°)+cos(-330°)
计算:sin315°-sin(-480°)+cos(-330°)

计算:sin315°-sin(-480°)+cos(-330°)
原式=sin(360°-45°)+sin480°+cos330°
=sin45°+sin(360°+120°)+cos(360°-30°)
=sin45°+sin120°+cos30°
=sin45°+sin(180°-60°)+cos30°
=sin45°+sin60°+cos30°
=(√2)/2+(1/2)+(√3)/2
=(1+√2+√3)/2

sin315°-sin(-480°)+cos(-330°)
=sin﹙360°-45°﹚+sin﹙360°+120°﹚+cos﹙360°-30°﹚
=sin﹙﹣45°﹚+sin120°+cos﹙﹣30°﹚
=-sin45°+sin60°+cos30°
=-√2/2+√3/2+√3/2
=√3-√2/2