ex \( \lim _{x \rightarrow 1}\left(\frac{2^{x}-2}{x-1}\right)= \)
ex \( f(x)=\left\{\begin{array}{ll}(-5)^{1-(1+x)^{2}} & ,-1 \leq x<1 \text {, cbs.on } \\ \frac{-1}{-1} & x=0 \\ \frac{-1}{\sin ^{-1} x} & , 0<x<1\end{array}\right. \)
\( \stackrel{\operatorname{ex}}{=} \lim _{x \rightarrow 2}\left(x \sqrt{20-x^{2}}\right) \)