3tan°cos30°+tan45°+sin30°-sin60°cos60°怎么解?
问题描述:
3tan°cos30°+tan45°+sin30°-sin60°cos60°怎么解?
答
解 3tan30°cos30°+tan45°+sin30°-sin60°cos60°
=3*√3/3*√3/2+1+1/2-√3/2*1/2
=3/2+1+1/2-√3/4
=3-√3/4