Problem 2. Define a function $g: \mathbb{Z} \to \mathbb{N}$ given by the rule $g(n) = \begin{cases} 2n + 1 & ; n \ge 0 \\ -2n & ; n < 0 \end{cases}$ (1) Get a feel for the behavior of this function by filling in the following table: \begin{tabular}{|c|c|} \hline n & g(n) \\ \hline -4 & \\ -3 & \\ -2 & \\ -1 & \\ 0 & \\ 1 & \\ 2 & \\ 3 & \\ 4 & \\ \hline \end{tabular} (2) Prove that $g$ is injective. (3) Prove that $g$ is surjective.
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Step 1: To get a feel for the behavior of the function g, we can start by plugging in some values of n into the function and observing the corresponding values of g(n). Show more…
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