(a+2b)(2a-b)-(a+2b)的2次方-(a-2b)的2次方，其中a=-3分之1，b=-3

Question

如题所述

Answer 1

(a+2b)(2a-b)-(a+2b)^2-(a-2b)^2
=(3 a - 10 b) b
=(3(-1/3)-10(-3))(-3)
=-87本回答被提问者采纳