求助数学解答题.关于因式分解(a+b)2(a-b)+(a-b)2(a+b)(x+y)2-4y2(m+2n)2+2(m+2n)(2m+n)+(2m+n)2x2+2xy+y2-4x-4y-5a4-a2-72x2-3x3-9+27x
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求助数学解答题.关于因式分解(a+b)2(a-b)+(a-b)2(a+b)(x+y)2-4y2(m+2n)2+2(m+2n)(2m+n)+(2m+n)2x2+2xy+y2-4x-4y-5a4-a2-72x2-3x3-9+27x
求助数学解答题.关于因式分解
(a+b)2(a-b)+(a-b)2(a+b)
(x+y)2-4y2
(m+2n)2+2(m+2n)(2m+n)+(2m+n)2
x2+2xy+y2-4x-4y-5
a4-a2-72
x2-3x3-9+27x
求助数学解答题.关于因式分解(a+b)2(a-b)+(a-b)2(a+b)(x+y)2-4y2(m+2n)2+2(m+2n)(2m+n)+(2m+n)2x2+2xy+y2-4x-4y-5a4-a2-72x2-3x3-9+27x
(a+b)2(a-b)+(a-b)2(a+b)
(x+y)2-4y2
=(x+y)^2 -(2y)^2
=(x+y+2y)(x+y-2y)
=(x+3y)(x-y)
(m+2n)2+2(m+2n)(2m+n)+(2m+n)2
=(m+2n+2m+n)^2 ,完全平方
=(3m+3n)^2
=9(m+n)^2
x2+2xy+y2-4x-4y-5
=(x^2+2xy+y^2)-(4x+4y)-5
=(x+y)^2-4(x+y)-5
=(x+y-5)(x+y+1)
a4-a2-72
=(a^2)^2 -a^2 -72
=(a^2 +8)(a^2 -9)
=(a^2 +8)(a+3)(a-3)
x2-3x3-9+27x
=(x^2 -9)-(3x^3 -27x)
=(x^2 -9)-3x(x^2 -9)
=(x^2 -9)(1-3x)
=(x+3)(x-3)(1-3x)