x^2-4xy+4y^2-9z^2
问题描述:
x^2-4xy+4y^2-9z^2
答
x^2-4xy+4y^2-9z^2 =(x-2y)^2 - (3z)^2=(x-2y+3z)(x-2y-3z)
x^2-4xy+4y^2-9z^2
x^2-4xy+4y^2-9z^2 =(x-2y)^2 - (3z)^2=(x-2y+3z)(x-2y-3z)