(1)计算:2sin60°+|-3|--()-1(2)化简:3(x2+2)-3(x+1)(x-1)
(1)计算: (2)先化简,再求值:,其中.
计算:.
计算:
计算: (1) (2)a(a-3)+(2-a)(2+a)
解方程: