\[\text{Найти}\ \ f'(x),\ \ \text{если}\ \ \ \ f(x) = \frac{x^2-5}{x^2-1}.\]
\[\Large f'(x) = \frac{8x}{(x^2-1)^2}\]
\[\large f'(x) = -\frac{8x}{(x^2-1)^2}\]
\[\large f'(x) = \frac{6x}{(x^2-1)^2}\]
\[f'(x) = 1\]