Question

Phân tích thành nhân tử :

a) \(x^2+5x-6\)

b) \(5x^2+5xy-x-y\)

c) \(7x-6x^2-2\)

Answer 1

a) \(x^2+5x-6\)

\(=x^2-2x+3x-6\\ =\left(x^2-2x\right)+\left(3x-6\right)\\ =x\left(x-2\right)+3\left(x-2\right)\\ =\left(x-2\right)\left(x+3\right)\)

b) \(5x^2+5xy-x-y\)

\(=\left(5x^2+5xy\right)-\left(x+y\right)\\ =5x\left(x+y\right)-\left(x+y\right)\\ =\left(x+y\right)\left(5x+1\right)\)

c)\(7x-6x^2-2\)

\(=3x+4x-6x^2-2\\ =\left(3x-6x^2\right)+\left(4x-2\right)\\ =3x\left(1-2x\right)+2\left(2x-1\right)\\ =3x\left(1-2x\right)-2\left(1-2x\right)\\ =\left(1-2x\right)\left(3x-2\right)\)

Answer 2

a, x² + 5x + 6

x²+2x+3x+6

x(x+2)+3(x+2)

(x+2)(x+3)

b,5x(x+y)-(x+y)

(x+y)(5x-1)

c,-6x²+7x-2

-6x² +3x+4x-2

-3x(2x-1)+2(2x-1)

(2x-1)(1-3x)