Question

把下列各式分解因式 x的平方-4y的平方-2x-4y

x的平方-4y的平方-2x-4y

(x-y)的平方+4xy

Answer 1

x^2-4y^2-2x-4y=(x+2y)(x-2y)-2(x+2y)=(x+2y)(x-2y-2)
(x-y)^2+4xy=x^2-2xy+y^2+4xy=x^2+2xy+y^2=(x+y)^2

Answer 2

x²-4y²-2x-4y
=(x+2y)(x-2y)-2x-4y
=(x+2y)(x-2y)-2(x+2y)
=(x+2y)(x-2y-2)

追问

因式分解
2a的平方+5ab+2b的平方

追答

2a2+5ab+2b2
=2a2+4ab+ab+2b2
=2(a+b)2+ab