分解因式x两次方(x-y)+y两次方(y-x)

问题描述:

分解因式x两次方(x-y)+y两次方(y-x)

X²(x-y)+y²(y-x )
= X²(x-y)-y²(x-y)
=(x-y)(X²- y² )
=(x-y)(X+Y)(X-Y)
=(x-y)²(x+y)