因式分解:(3x+y)^2-(x-3y)^2
问题描述:
因式分解:(3x+y)^2-(x-3y)^2
答
(3x+y)^2-(x-3y)^2
=[(3x+y)+(x-3y)][(3x+y)-(x-3y)]
=(4x-2y)(2x+4y)
=4(2x-y)(x+2y)