Phân tích đa thức thành nhân tử
2x^3-2xy^2-8x^2+8xy
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(2x^3-2xy^2-8x^2+8xy\)
\(=2x\left(x^2-y^2-4x+4y\right)\)
\(=2x\left[\left(x^2-y^2\right)-4\left(x-y\right)\right]\)
\(=2x\left[\left(x-y\right)\left(x+y\right)-4\left(x-y\right)\right]\)
\(=2x\left(x-y\right)\left(x+y-4\right)\)
2x^3 - 2xy^2 - 8x^2 + 8xy
= 2x^2 ( x - y ) - 8x ( x - y )
= ( x - y ) ( 2x^2 - 8x )
= ( x - y ) 2x ( x - 4 )
![](https://rs.olm.vn/images/avt/0.png?1311)
\(2x^3-3x^2+3x-1\)
\(=2x^3-x^2-2x^2+x+2x-1\)
\(=x^2\left(2x-1\right)-x\left(2x-1\right)+\left(2x-1\right)\)
\(=\left(2x-1\right)\left(x^2-x+1\right)\)
![](https://rs.olm.vn/images/avt/0.png?1311)
Lời giải:
$2x^2+3x-5=(2x^2-2x)+(5x-5)=2x(x-1)+5(x-1)=(x-1)(2x+5)$
![](https://rs.olm.vn/images/avt/0.png?1311)
\(=2\left(x^2-y^2\right)-3\left(x+y\right)=2\left(x-y\right)\left(x+y\right)-3\left(x+y\right)=\left(x+y\right)\left(2x-2y-3\right)\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(5x^2-10x+2x-4\)
\(=5x\left(x-2\right)+2\left(x-2\right)\)
\(=\left(x-2\right)\left(5x+2\right)\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a)
\(2x^2y-8xy^2\\ =2xy\left(x-4y\right)\)
b)
\(x^2-2xy+y^2-16\\ =\left(x^2-2xy+y^2\right)-16\\ =\left(x-y\right)^2-16\\ =\left(x-y-4\right)\left(x-y+4\right)\)
![](https://rs.olm.vn/images/avt/0.png?1311)
Phân tích đa thức thành nhân tử :
8x3 - 8x2y + 2xy2
= 8x3 - 4x2y - 4x2y + 2xy2
= 4x2( x - y ) - 2xy ( x - y )
= ( x - y)(4x2 - 2xy)
= 2x(x - y)(2x - y)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) \(2x^2+5x+2\)
\(=2x^2+4x+x+2\)
\(=2x\left(x+2\right)+\left(x+2\right)\)
\(=\left(x+2\right)\left(2x+1\right)\)
b) \(4x^2-4x-9y^2+12y-3\)
\(=\left(4x^2-4x+1\right)-\left(9y^2-12y+4\right)\)
\(=\left(2x-1\right)^2-\left(3y-2\right)^2\)
\(=\left(2x-1+3y-2\right)\left(2x-1-3y+2\right)\)
\(=\left(2x+3y-3\right)\left(2x-3y+1\right)\)
c) \(x^4-2x^3-4x^2+4x-3\)
\(=x^4+x^3-x^2+x-3x^2-3x+3x-3\)
\(=\left(x^4+x^3-x^2+x\right)-\left(3x^2+3x-3x+3\right)\)
\(=x\left(x^3+x^2-x+1\right)-3\left(x^3+x^2-x+1\right)\)
\(=\left(x^3+x^2-x+1\right)\left(x-3\right)\)
d) \(x^3-x+3x^2y+3xy^2+y^3-y\)
\(=\left(x^3+3x^2y+3xy^2+y^3\right)-\left(x+y\right)\)
\(=\left(x+y\right)^3-\left(x+y\right)\)
\(=\left(x+y\right)\left[\left(x+y\right)^2-1\right]\)
\(=\left(x+y\right)\left(x+y-1\right)\left(x+y+1\right)\)
\(2x^3-2xy^2-8x^2+8xy=2x\left(x^2-y^2\right)-8x\left(x-y\right)=2x\left(x-y\right)\left(x+y\right)-8x\left(x-y\right)=2x\left(x-y\right)\left(x+y-4\right)\)
\(2x^3-2xy^2-8x^2+8xy\)
\(=2x\left(x^2-y^2\right)-8x\left(x-y\right)\)
\(=2x\left(x+y\right)\left(x-y\right)-8x\left(x-y\right)\)
\(=\left[2x\left(x+y\right)-8x\right]\left(x-y\right)\)
\(=2x\left(x+y-4\right)\left(x-y\right)\)