a, \(6x^2-11x+3\Leftrightarrow6x^2-9x-2x+3\Leftrightarrow\left(6x^2-9x\right)-\left(2x-3\right)\Leftrightarrow3x\left(2x-3\right)-\left(2x-3\right)\Leftrightarrow\left(3x-1\right)\left(2x-3\right)\)
Thk mấy cái bài này nhứt nè!
a) \(6x^2-11x+3\) = \(\left(6x^2-2x\right)-\left(9x-3\right)\)
= \(2x\left(3x-1\right)-3\left(3x-1\right)\)
= \(\left(3x-1\right)\left(2x-3\right)\)
b) \(2x^2+3x-27\) = \(\left(2x^2-6x\right)+\left(9x-27\right)\)
= \(2x\left(x-3\right)+9\left(x-3\right)\)
= \(\left(x-3\right)\left(2x+9\right)\)
c) \(x^2+2x-3=\left(x^2-x\right)+\left(3x-3\right)\)
= \(x\left(x-1\right)+3\left(x-1\right)\)
= \(\left(x-1\right)\left(x+3\right)\)
\(2x^2+3x-27\Leftrightarrow2x^2-6x+9x-27\Leftrightarrow\left(2x^2-6x\right)+\left(9x-27\right)\Leftrightarrow2x\left(x-3\right)+9\left(x-3\right)\Leftrightarrow\left(2x+9\right)\left(x-3\right)\)c,\(x^3+2x-3\Leftrightarrow x^3-x+3x-3x\Leftrightarrow x\left(x^2-1\right)+3\left(x-1\right)\Leftrightarrow x\left(x+1\right)\left(x-1\right)+3\left(x-1\right)\Leftrightarrow\left(x-1\right)\left(x^2+x+3\right)\)
Câu c tui nhầm đề! Sửa lại:
\(x^3+2x-3=x^3-x^2+x^2-x+3x-3\)
= \(x^2\left(x-1\right)+x\left(x-1\right)+3\left(x-1\right)\)
= \(\left(x-1\right)\left(x^2+x+3\right)\)
a,
\(6x^2-11x+3\\ =6x^2-2x-9x+3\\ =2x\left(3x-1\right)-3\left(3x-1\right)\\ =\left(3x-1\right)\left(2x-3\right)\)
b,
\(2x^2+3x-27\\ =2x^2-6x+9x-27\\ =2x\left(x-3\right)+9\left(x-3\right)\\ =\left(x-3\right)\left(2x+9\right)\)
c
,\(x^3+2x-3\\ =x^3-x^2+x^2-x+3x-3\\ =x^2\left(x-1\right)+x\left(x-1\right)+3\left(x-1\right)\\ =\left(x-1\right)\left(x^2+x+3\right)\)
(1) 6x2 - 11x + 3 = 6x2 - 2x -9x +3 = (6x2 - 9x) - (2x -3) = 3x(2x-3)-(2x-3)=(2x-3)(3x-1)
(2) 2x2 + 3x -27 = 2x2 -6x+9x -27 = (2x2 - 6x) +(9x-27) = 2x(x-3)+9(x-3)=(x-3)(2x+9)
(3) De sai , Sua lai :X2 + 2x -3 :
x2 +2x-3 = x2 -x +3x -3 = (x2 + 3x) - (x+3) = x(x+3)-(x+3)=(x+3)(x-1)
