y的四次方-y² 3ax²-3ay² 4x³-8x²+4x
问题描述：
y的四次方-y² 3ax²-3ay² 4x³-8x²+4x
y的四次方-y² 3ax²-3ay² 4x³-8x²+4x a²-2a（b+c）+（b+c）²
答
(1)y的四次方-y²y²(y²-1)=y²(y-1)(y+1)(2)3ax²-3ay²3a(x²-y²)=3a(x-y)(x+y)(3)4x³-8x²+4x4x(x²-2x+1)=4x(x-1)²(4)a²-2a（b+c）+（b+c）² {a...