Question

计算： cos45°+sin30° sin30°?tan45° + tan 2 60°-2tan60°+1

计算： cos45°+sin30° sin30°?tan45° + tan 2 60°-2tan60°+1 ．

Answer 1

原式= 2 2 + 1 2 1 2 × 2 2 + (tan60°-1) 2 = 2 +1 2 2 4 + 3 -1 = 2 +1 2 × 4 2 + 3 -1 =2+ 2 + 3 -1 =1+ 2 + 3 ．