Question

Phân tích đa thức thành nhân tử : x^2 - 9 - (x-3) (5-2x)

Answer 1

\(=\left(x-3\right)\left(x+3\right)+\left(x-3\right)\left(2x-5\right)\\ =\left(x-3\right)\left(x+3+2x-5\right)\\ =\left(x-3\right)\left(3x-2\right)\)

Answer 2

\(x^2-9-\left(x-3\right)\left(5-2x\right)=\left(x-3\right)\left(x+3\right)-\left(x-3\right)\left(5-2x\right)=\left(x-3\right)\left(x+3-5+2x\right)=\left(x-3\right)\left(3x-2\right)\)

Answer 3

\(x^2-9-\left(x-3\right)\left(5-2x\right)\\ =\left(x^2-9\right)-\left(x-3\right)\left(5-2x\right)\\ =\left(x-3\right)\left(x+3\right)-\left(x-3\right)\left(5-2x\right)\\ =\left(x-3\right)\left(x+3-5+2x\right)\\ =\left(x-3\right)\left(3x-2\right)\)

Answer 4

\(x^2-9-\left(x-3\right)\left(5-2x\right)\)

\(=\left(x-3\right)\left(x+3\right)-\left(x-3\right)\left(5-2x\right)\)

\(=\left(x-3\right)\left[\left(x+3\right)-\left(5-2x\right)\right]\)

\(=\left(x-3\right)\left(x+3-5+2x\right)\)

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

#RQT