Lời giải

Đáp án đúng là: C

$\frac{{\left( {5x{\rm{ }} + {\rm{ }}3} \right)P}}{{5x - 3}} = \frac{{\left( {2x - 1} \right)Q}}{{25{x^2} - 9}}$

$\frac{{\left( {5x + 3} \right)P}}{{5x - 3}} = \frac{{\left( {2x - 1} \right)Q}}{{\left( {5x + 3} \right)\left( {5x - 3} \right)}}$

$\left( {5x{\rm{ }} + {\rm{ }}3} \right)P\left( {5x{\rm{ }} + {\rm{ }}3} \right)\left( {5x - 3} \right) = \left( {2x - 1} \right)Q\left( {5x - 3} \right)$

${\left( {5x + 3} \right)^2}P = \left( {2x - 1} \right)Q$.

Do đó $\frac{P}{Q} = \frac{{2x - 1}}{{{{\left( {5x + 3} \right)}^2}}}$.