答案 1.A 2.C 3.C 4.C 5.D 6.A 7.B 8.B 9.A 10.D 11.2
12.-6x+2y-1
13.1+x+x2+x3+x4+x5+x6+x7 1-xn+1 14.5
15.(1)2a6b9;(2)?4xy?8y2
16.(1)m??15,(2)512. 17.(1)16a2+56ab+24b2;(2)5a2+
352ab+152b2
18.(1)a2?b2 (2)?a?b??a?b? (3)a2?b2??a?b??a?b?19.(1)a?2b;(2)13
4)101200 (
相关推荐: