Thực hiện phép tính.

* Hướng dẫn giải

a) \(\frac{x}{{x - 3}} + \frac{{9 - 6x}}{{x(x - 3)}} = \frac{{{x^2} + 9 - 6x}}{{x(x - 3)}}\)

\(\frac{{{{(x - 3)}^2}}}{{x(x - 3)}} = \frac{{x - 3}}{x}\)

b) \(\frac{{6x - 3}}{x}:\frac{{4{x^2} - 1}}{{3{x^2}}} = \frac{{6x - 3}}{x}.\frac{{3{x^2}}}{{4{x^2} - 1}}\)

\(\begin{array}{l}
 = \frac{{3(2x - 1).3{x^2}}}{{x(2x - 1)(2x + 1)}}\\
 = \frac{{9x}}{{2x + 1}}
\end{array}\)