## Precalculus (10th Edition)

amplitude: $2$ period: $2\pi$
If a function has form $y=A\cos(\omega x)$, then there $|A|$ stands for the amplitude. First we identify $\omega$ and $A$ from the form of $y=A\sin{(\omega x)}$. Hence $A=2$, $\omega=1.$ To get the period $T$, we can use the formula $T=\frac{2\pi}{\omega}$ to obtain: $T=\frac{2\pi}{1}=2\pi$