问题
解答题
计算或化简: (1)(
(2)(a+1)2-2(a+1)(a-1)-6 (3)a-a2-a3+(-2a3)2-a8÷a2 (4)(a-b+1)(a+b-1) |
答案
(1)原式=2-1+1
=2;
(2)原式=a2+2a+1-2a2+2-6
=-a2+2a-3;
(3)原式=a6+4a6-a6
=4a6;
(4)原式=[a-(b-1)][a+(b-1)]
=a2-(b-1)2
=a2-b2+2b-1.