lim -> 1 [tex] \frac{2}{{x}^{2} - 1 } - \frac{1}{ x - 1} [/tex] hasil & caranya?

[tex]lim -> 1
\: \frac{2}{{x}^{2} - 1 } - \frac{1}{ x - 1} \\ \frac{2}{ {x}^{2} - 1} - \frac{ {x} + 1}{ {x}^{2} - 1} = \frac{1 - x}{ {x}^{2} - 1 } = \frac{( - x + 1)}{(x + 1)(x - 1)} = \frac{ - 1}{(x + 1)} \\ \frac{ - 1}{1 + 1} = \frac{ - 1}{2} [/tex]