a)
\(3x^2-11x+6\)
\(=3x^2-9x-2x+6\)
\(=3x\left(x-3\right)-2\left(x-3\right)\)
\(=\left(x-3\right)\left(3x-2\right)\)
b)
\(8x^2+10x-3\)
\(=8x^2-2x+12x-3\)
\(=8x\left(x-\frac{1}{4}\right)+12\left(x-\frac{1}{4}\right)\)
\(=\left(8x+12\right)\left(x-\frac{1}{4}\right)\)
\(=\left(2x+2\right)\left(4x-1\right)\)
c)
\(8x^2-2x-1\)
\(=8x^2-4x+2x-1\)
\(=8x\left(x-\frac{1}{2}\right)+2\left(x-\frac{1}{2}\right)\)
\(=\left(x-\frac{1}{2}\right)\left(8x+2\right)\)
\(=\left(2x-1\right)\left(4x+1\right)\)
a. 3x^2-11x + 6
= 3x^2 - 9x - 2x +6
= 3x(x-3) - 2(x-3)
= (x-3)(3x-2)
b. 8x^2 + 10x -3
= 4x ( 2x +3 ) - ( 2x+3)
= ( 2x+3) (4x-1)
c. 8x^2 - 2x -1
= 4x( 2x -1 ) + (2x-1)
= ( 4x +1 ) ( 2x-1)
bạn ơi câu a bạn có chép sai đề bài không ạ?
a) \(3x^2-11x+6\\ =3x^2-9x-2x+6\\ =3x\left(x-3\right)-2\left(x-3\right)\\ =\left(x-3\right)\left(3x-2\right)\)
b) \(8x^2+10x-3\\ =8x^2\left(x-\frac{1}{4}\right)+12\left(x-\frac{1}{4}\right)\\ =\left(8x+12\right)\left(x-\frac{1}{4}\right)\\ =\left(2x+12\right)\left(x-\frac{1}{4}\right)\\ =\left(2x+2\right)\left(4x-1\right)\)
c) \(8x^2-2x-1\\ =8x^2-4x+2x-1\\ =8x\left(x-\frac{1}{2}\right)+2\left(x-\frac{1}{2}\right)\\ =\left(x-\frac{1}{2}\right)\left(8x+2\right)\\ =\left(2x+1\right)\left(4x+1\right)\)
