习题15.4 因式分解 5,(3)4xy²-4x²y-y ³ (4)3ax²-3ay²
问题描述:
习题15.4 因式分解 5,(3)4xy²-4x²y-y ³ (4)3ax²-3ay²
答
4xy²-4x²y-y ³
=-y(-4xy+4x^2+y^2)
=-y(2x-y)^2
3ax²-3ay²
=3a(x^2-y^2)
=3a(x+y)(x-y)