Question

1. Phân tích đa thức thành nhân tử:

a) 3x ² -3xy - 5x + 5y

b) x ² + 4x – 45

Answer 1

Answer 2

Answer 3

a,\(3x^2-3xy-5x+5y\)

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

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

b, \(x^2+4x-45\)

\(=x^2+9x-5x-45\)

\(=x\left(x-5\right)+9\left(x-5\right)\)

\(=\left(x-5\right)\left(x+9\right)\)

Answer 4

3x ² -3xy - 5x + 5y

=(3x²-3xy)-(5x-5y)

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

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

b) x ² + 4x – 45

=x²+9x-5x-45

=(x²+9x)-(5x+45)

=x(x-9)-5(x-9)

=(x-9)(x-5)