分解因式 @.-16x^4-x^2y^2 @.4x^2-1/4y^2 @ax^2-ay^2 @ x^2y-9y@号是用来分开的

问题描述:

分解因式 @.-16x^4-x^2y^2 @.4x^2-1/4y^2 @ax^2-ay^2 @ x^2y-9y
@号是用来分开的

@.-16x^4-x^2y^2 =-x²(16x²+y²)@.4x^2-1/4y^2 =(2x²+1/2y²)(2x²-1/2y²)@ax^2-ay^2 =a(x²-y)²=a(x+y)(x-y)@ x^2y-9y=y(x²-9)=y(x+3)(x-3)