题目内容
解:原式=[(a3)2-(a-3)2]÷[(a4+a-4+1)(a-a-1)]
(1)÷÷;
(2)(x-1+x+x0);
(3);
(4) (a3+a-3)(a3-a-3)÷[(a4+a-4+1)(a-a-1)].