Gửi bạn:

$\dfrac{2}{3x}+\dfrac{1}{2x-2}+\dfrac{4-x}{6x^2-6x}$ 

$=\dfrac{2}{3x}+\dfrac{1}{2(x-1)}+\dfrac{4-x}{6x(x-1)}$ 

$=\dfrac{2.2(x-1)}{3x.2.(x-1)}+\dfrac{1.3x}{2.3x.(x-1)}+\dfrac{4-x}{6x(x-1)}$

$=\dfrac{4(x-1)}{6x(x-1)}+\dfrac{3x}{6x(x-1)}+\dfrac{4-x}{6x(x-1)}$ 

$=\dfrac{4x-4}{6x(x-1)}+\dfrac{3x}{6x(x-1)}+\dfrac{4-x}{6x(x-1)}$ 

$=\dfrac{4x-4+3x+4-x}{6x(x-1)}$ 

$=\dfrac{6x}{6x(x-1)}$ 

$=\dfrac{1}{x-1}$ 

Đáp án + giải thích các bước giải:

`a, 2/(3x) + 1/(2x - 2) + (4 - x)/(6x^2 - 6x)`

` = 2/(3x) + 1/(2(x - 1)) + (4 - x)/( 6x(x - 1))`

` = (4(x - 1))/( 6x(x - 1) ) + (3x)/( 6x(x - 1) ) + (4 - x)/( 6x(x - 1) )`

` = (4x - 4 + 3x + 4 - x)/( 6x(x - 1) )`

` = (6x)/(6x(x - 1))`

` = 1/(x - 1)`