$\frac{3x−1}{x-1}$ - $\frac{2x+5}{x+3}$ = 1- $\frac{4}{(x-1)(x+3)}$ ĐKXĐ : x $\neq$ 1 ; x $\neq$ -3
=> (3x−1)(x+3) - (2x+5)(x-1) = (x-1)(x+3) - 4
<=> $3x^{2}$ +9x - x -3 - $2x^{2}$ -2x +5x -5 = $x^{2}$ +3x -x-3 -4
<=> ( $3x^{2}$ - $2x^{2}$ - $x^{2}$ ) + ( 9x -x -2x + 5x -3x + x)= 3 + 5 -3 -4
<=> 9x = 1
<=> x = $\frac{1}{9}$