Question

Phân tích các đa thức sau thành nhân tử :
a, 4x^2 - 6x
b, 9x^4y^3 + 3x^2y^4
c, 3 ( x-y) - 5x ( y-x)
d, x^3 - 2x^2 + 5x
e, 5( x + 3y ) - 15x ( x + 3y )
f, 2x^2 ( x+1) + 4 ( x +1 )

Answer 1

a) Ta có: \(4x^2-6x\)

\(=2x\left(2x-3\right)\)

b) Ta có: \(9x^4y^3+3x^2y^4\)

\(=3x^2y^3\left(3x^2+y\right)\)

c) Ta có: 3(x-y)-5x(y-x)

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

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

d) Ta có: \(x^3-2x^2+5x\)

\(=x\left(x^2-2x+5\right)\)

e) Ta có: \(5\left(x+3y\right)-15x\left(x+3y\right)\)

\(=\left(x+3y\right)\left(5-15x\right)\)

\(=5\left(x+3y\right)\cdot\left(1-3x\right)\)

f) Ta có: \(2x^2\left(x+1\right)+4\left(x+1\right)\)

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

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