Question

Phân tích đa thức thành nhân tử:
a) 2x³y - 8x²y + 8xy

b) 3x(x+5) - 2(5+x)
c) x(y²+1) + 4(1+y²)

d) (2x-3)² - 25y²

^{Giúp e với ạ!!}

Answer 1

a: \(2x^3y-8x^2y+8xy\)

\(=2xy\cdot x^2-2xy\cdot4x+2xy\cdot4\)

\(=2xy\left(x^2-4x+4\right)=2xy\left(x-2\right)^2\)

b: 3x(x+5)-2(5+x)

=3x(x+5)-2(x+5)

=(x+5)(3x-2)

c: \(x\left(y^2+1\right)+4\left(y^2+1\right)\)

\(=\left(y^2+1\right)\left(x+4\right)\)

d: \(\left(2x-3\right)^2-25y^2\)

\(=\left(2x-3\right)^2-\left(5y\right)^2\)

=(2x-3-5y)(2x-3+5y)

Answer 2

\(a)2x^3y-8x^2y+8xy =2xy.x^2-8x^2y+2xy.4 =2xy(x^2-4x+4) =2xy(x-2)^2\)

\(b)3x(x+5)-2(5+x) =(x+5)(3x-2)\)

\(c) \)\(x\left(y^2+1\right)+4\left(1+y^2\right)=\left(1+y^2\right)\left(x+4\right)\)

\(d)(2x-3)^2-25y^2 =(2x-3)^2-(5y)^2 =(2x-3-5y)(2x-3+5y)\)