因式分解(1)x^3-xy^2+x^2-y^2 (2)x^4-6x^2y^2+9y^4 ( 3 )4x^2-4xy+y^2-81

问题描述:

因式分解(1)x^3-xy^2+x^2-y^2 (2)x^4-6x^2y^2+9y^4 ( 3 )4x^2-4xy+y^2-81
快点呐 在线等=v=!~

(1)x^3-xy^2+x^2-y^2
==x^2(x+1)-y^2(x+1)
==(x+1)(x^2-y^2)
==(x+1)(x-y)(x+y)

(2)x^4-6x^2y^2+9y^4
==(x^2-3y^2)^2

( 3 )4x^2-4xy+y^2-81
==(2x+y)^2-81
==(2x+y-9)(2x+y+9)