-8x^2y-2x^3-8xy^2因式分解

题目

-8x^2y-2x^3-8xy^2因式分解
-8x^2y-2x^3-8xy^2
6a^2-a-9a^3
(x-y)^2+12(x-y)+36
25(x-y)^2-60(x-y)+36
(x+y)^2-2(x^2-y^2)+(x-y)^2
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答案

-8x^2 y-2x^3-8xy^2
=(-2x)(4xy+4y^2 )-2x^3
=(-2x)(4y^(2+) 4xy+x^2 )
=(-2x) (2y+x)^2
6a^2-a-9a^3
=-9a^3+6a^2-a
=a(-9a^2+6a-1)
=a(3a-1)(-3a+1)
(x-y)^2+12(x-y)+36
=(x-y+6)^2
25(x-y)^2-60(x-y)+36
=(5x-5y-6)^2
(x+y)^2-2(x^2-y^2)+(x-y)^2
=(x+y)^2-2(x+y)(x-y)+(x-y)^2
=[(x+y)-(x-y) ]^2
=(2y)^2
=4y^2