[질문] x²－2x＋2y－y²를인수분해를하면어떻게나오나요

답변이늦어죄송합니다T_T★x²－y²－2x＋2y=(합차공식에의해) (x+y)(x-y)-2x+2y=뒷부분을 (-2)로묶으면 -2(x+y)(x-y)(x-y)=-2(x+y)(x-y)²입니다^__^