Giải thích các bước giải:
a)
\(\frac{{{{(x + 5)}^2} - 9}}{{{x^2} + 4x + 4}} = \frac{{{x^2} + 10x + 25 - 9}}{{{{(x + 2)}^2}}} = \frac{{{x^2} + 10x + 16}}{{{{(x + 2)}^2}}} = \frac{{(x + 2)(x + 8)}}{{{{(x + 2)}^2}}} = \frac{{x + 8}}{{x + 2}}\)
b)
\(\begin{array}{l}
2 - \frac{x}{{x - 6}} + \frac{{36}}{{{x^2} - 6x}} = \frac{{2x - 12 - x}}{{x - 6}} + \frac{{36}}{{x(x - 6)}}\\
= \frac{{x - 12}}{{x - 6}} + \frac{{36}}{{x(x - 6)}} = \frac{{{x^2} - 12x + 36}}{{x(x - 6)}} = \frac{{{{(x - 6)}^2}}}{{x(x - 6)}} = \frac{{x - 6}}{x}
\end{array}\)
