如图,CA=CD,∠B=∠E,∠BCE=∠ACD.求证:AB=DE.
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)-