Answer
$y=-\frac{5}{2}cos(\pi x)$
Work Step by Step
1. Based on the given graph, we can initially identify that it resembles a graph of negative cosine.
2. We can determine the amplitude $|A|=\frac{5}{2}$, period $p=2$, passing $(0,-\frac{5}{2})$.
3. Write a model as $y=-\frac{5}{2}cos(\omega x)$
4. We have $\frac{2\pi}{\omega}=2$, thus $\omega=\pi$
5. The equation is $y=-\frac{5}{2}cos(\pi x)$
