Question

(每小题7分，共l4分)   
(1)计算：-2-()^-1×+(1-)⁰；
(2)化简：(a+2)(a-2)-(a-2)²．

Answer 1

(1)解：原式=一2一×2+1              ……3分
=一2—2+1                        ……5分
=一3．                           ……7分
(2)解：原式=a²一4一(a²一4a+4)                      ……4分
= a²一4一a²+4a一4                       ……6分
=4a一8．                                 ……7分解析:
略