# What is the period and amplitude for y=sin(2x) ?

$y = 1 \cdot \sin \left(2 x\right)$
$1$ is the amplitude meaning that your function is oscillating between $+ 1 \mathmr{and} - 1$;
$2$ is used to evaluate the period as: $p e r i o d = \frac{2 \pi}{\textcolor{red}{2}} = \pi$ so that one complete oscillation of your sine function is "squeezed" inside the interval $0$ to $\pi$.