一道初中的分解因式，急，在线等

（x^2+xy+y^2)(x^2+xy+3y^2)+y^4

换元 x^2+xy=a

(a+y^2)(+3y^2)+y^4
=a^2+4y^2a+4y^4
=(a+2y^2)^2
=(x^2+xy+2y^2)^2
这是一种常见题型，熟练的话，换元这一步可以省略。

怎么又加一道题啊。。。

X^4-8XY^3+3X^3Y-6X^2Y^2
=(X^4-8XY^3)+(3X^3Y-6X^2Y^2)
=x(x^3-8y^3)+3x^2*y*(x-2y)
=x(x-2y)(x^2+2xy+4y^2)+3x^2*y*(x-2y)
=x(x-2y)[x^2+5xy+4y^2]
=x(x-2y)(x+y)(x+4y)

（x^2+xy+y^2）（x^2+xy+3y^2）+y^4
=(x^2+xy)^2+4y^2*(x^2+xy)+3y^4+y^4
=(x^2+xy)^2+2*(2y^2)*(x^2+xy)+(2y^2)^2
=(x^2+xy+2y^2)^2

X^4-8XY^3+3X^3Y-6X^2Y^2
=(X^4-8XY^3)+(3X^3Y-6X^2Y^2)
=x(x^3-8y^3)+3x^2*y*(x-2y)
=x(x-2y)(x^2+2xy+4y^2)+3x^2*y*(x-2y)
=x(x-2y)[x^2+5xy+4y^2]
=x(x-2y)(x+y)(x+4y)

（x^2+xy+y^2）（x^2+xy+3y^2）+y^4
=（x^2+xy+2y^2-y^2）（x^2+xy+2y^2+y^2）+y^4
=（x^2+xy+2y^2)^2-y^4+y^4
X^4-8XY^3+3X^3Y-6X^2Y^2
=x(x-2y)(x^2+2xy+4y^2)+3x^2y(x-2y)
=x(x-2y)(x^2+2xy+4y^2+3xy)
=x(x-2y)(x+y)(x+4y)

(x^4)+2(x^