(a-b)+x平方(b-a)
=(a-b)-x^2(a-b)
=(a-b)(1-x^2)
=(a-b)(1-x)(1+x)
4M平方—(m+n)平方
=(2m)^2-(m+n)^2
=(2m-m-n)(2m+m+n)
-(m-n)(3m+n)
(x-y)平方-2(y-x)+1
=(x-y)^2+2(x-y)+1
=(x-y+1)^2
-4a平方x平方+8ax-4
=-4[(ax)^2-2ax+1)
=-4(ax-1)^2
(a-b)+x平方(b-a)
=(a-b)-x^2(a-b)
=(a-b)(1-x^2)
=(a-b)(1-x)(1+x)
4M平方—(m+n)平方
=(2m)^2-(m+n)^2
=(2m-m-n)(2m+m+n)
-(m-n)(3m+n)
(x-y)平方-2(y-x)+1
=(x-y)^2+2(x-y)+1
=(x-y+1)^2
-4a平方x平方+8ax-4
=-4[(ax)^2-2ax+1)
=-4(ax-1)^2