Question

phân tích đa thức thành nhân tử: x²+2x+1-y²+2y-1

 

 

Answer 1

`x^2+2x+1-y^2+2y-1`

`=(x^2+2x+1)-(y^2-2y+1)`

`=(x+1)^2-(y-1)^2`

`=(x+1+y-1)(x+1-y+1)`

`=(x+y)(x-y+2)`

Answer 2

Ta có: \(x^2+2x+1-y^2+2y-1\)

\(=\left(x+1\right)^2-\left(y-1\right)^2\)

\(=\left(x+1-y+1\right)\left(x+1+y-1\right)\)

\(=\left(x-y+2\right)\left(x+y\right)\)