- Bijection Proof (a taste of math proof)blackpenredpenLet \(f : \mathbb{N} \rightarrow \mathbb{Z},\)\(f(n) = \begin{cases} \dfrac{n}{2} & \text{if }n\text{ is even} \\[0.75em] \dfrac{-(n + 1)}{2} & \text{if }n\text{ is odd.} \end{cases}\)Prove that \(f\) is bijective.