cos60°+sin45°×cos45°-tan60°×tan30°=?
问题描述：
cos60°+sin45°×cos45°-tan60°×tan30°=?
cos45°-cos60°分之1+sin30°分之1+cos²30°+sin²45°=?
3tan30°+cot45°+cos30°+2sin60°-2tan45°=?
答
cos60°+sin45°×cos45°-tan60°×tan30°=1/2+(√2)/2×(√2)/2-√3×(√3)/3=1/2+1/2-1=0cos45°-cos60°分之1+sin30°分之1+cos²30°+sin²45°=(√2)/2-2+2+3/4+1/2=(2√2)/4+3/4+2/4=(2√2+5)/43tan...