(1)1-x²+2xy-y² (2)x²-y²-z²-2yz 分解因式

问题描述:

(1)1-x²+2xy-y² (2)x²-y²-z²-2yz 分解因式

(1)1-x²+2xy-y²
=1-(x-y)²
=(1-x+y)(1+x-y)
(2)x²-y²-z²-2yz
=x²-(y+z)²
=(x+y+z)(x-y-z)