1、因式分解:a^2(a-b)+(b-a) 已知x+y=2,xy=2/3,求:(x-y)^2
问题描述:
1、因式分解:a^2(a-b)+(b-a) 已知x+y=2,xy=2/3,求:(x-y)^2
答
1.a^2(a-b)+(b-a)
=(a^2-1)(a-b)
=(a+1)(a-1)(a-b)
2.(x-y)^2
=(x+y)^2-4xy
=4-8/3
=4/3