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\noindent{\Large{\textsc{Number Theory\hfill Assignment 5.3  \\ Fall 2020 \hfill Due September 30}}}

\large

\vspace{1cm}


\begin{exercise}
Let $G$ be a group.  For $a \in G$ define $L_a :G \to G$ by $L_a(x) = ax$.  Prove that $L_a$ is a bijection by showing that $(L_a)^{-1} = L_{a^{-1}}$.
\end{exercise}

\begin{exercise}
Textbook exercises 5.2.2(b) and 5.2.4(c).
\end{exercise}

\begin{exercise}
Textbook exercise 5.2.12.
\end{exercise}

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