计算: ( - 2 ) 2 - 9 + ( 2 - 1 ) 0 + ( 1 3 ) - 1 .
计算:
计算:.
(1)计算:; (2)因式分解:.
计算: (1) (2)
(本题满分8分,每题4分)计算: (1)+2sin45°- (2)2(a+1)-(3-a)(3+a)-