第1个回答 2018-05-20
1.( x2+y2)(x+y)(x-y) (2x-y) y.y y
________________ * ____________ *_____ 结果 ________
(2x-y)(x+y) (x-y)y ( x2+y2)2 (x2+y2)
2. (1-n) mn mn
_______* _____ 结果 _____ (m-n) (n-1) n-m
3. (a+b) (a+2b) a+2b
_______* _______ 结果 _______
a (a+b) a