\[\frac{a^{2} + 2a + 1}{a^{2} - 1} = \frac{(a + 1)^{2}}{(a - 1)(a + 1)} =\]
\[= \frac{a + 1}{a - 1};\ \ \ \ a = - 0,5:\]
\[\frac{- 0,5 + 1}{- 0,5 - 1} = \frac{0,5}{- 1,5} = - \frac{5}{15} = - \frac{1}{3}.\]