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\begin{document}

Find the limits for the following
indeterminate forms of the type ``$\infty - \infty$''.

\begin{enumerate}

\item $\lim\limits_{x \to 0} {{1 \over {\sin x}}- {1 \over x}}\,$.

\item $\lim\limits_{x \to 0} {{1 \over {x^2}} - {1 \over x}}\,$.

\item $\lim\limits_{x \to 0} {{{1+x} \over x} - {{1-x}
\over x}}\,$.

\end{enumerate}

\end{document}