$\frac{2}{3x+1}$ - $\frac{15}{6x^2-x-1}$ = $\frac{3}{2x-1}$

$\text{$\dfrac{2}{3x + 1}$ - $\dfrac{15}{6x² - x - 1}$ = $\dfrac{3}{2x - 1}$ Đkxđ: x $\neq$ -$\dfrac{1}{3}$; x $\neq$ $\dfrac{1}{2}$ }$

$\text{⇔ $\dfrac{2}{3x + 1}$ - $\dfrac{15}{6x² - 3x + 2x - 1}$ = $\dfrac{3}{2x - 1}$ }$

$\text{⇔ $\dfrac{2}{3x + 1}$ - $\dfrac{15}{3x(2x - 1) + (2x - 1)}$ = $\dfrac{3}{2x - 1}$ }$

$\text{⇔ $\dfrac{2}{3x + 1}$ - $\dfrac{15}{(3x + 1)(2x - 1)}$ = $\dfrac{3}{2x - 1}$ }$

$\text{⇔ $\dfrac{2(2x - 1) - 15}{(3x + 1)(2x - 1)}$ = $\dfrac{3(3x + 1)}{(3x + 1)(2x - 1)}$}$

$\text{⇒ 4x - 2 - 15 = 9x + 3}$

$\text{⇔ 4x - 9x = 3 + 2 + 15}$

$\text{⇔ -5x = 20}$

$\text{⇔ x = -4 (t/m)}$

$\text{Vậy phương trình có tập nghiệm là S = {-4}}$

$\textit{Ha1zzz}$