# What is the period and amplitude for y = 7cos (4pix-2)?

The Amplitude is $7$ meaning that your $\cos$ oscilates between $+ 7$ and $- 7$.
The Period can be found using the $4 \pi$ multiplying the $x$ in the argument of $\cos$ as:
period=$\frac{2 \pi}{\textcolor{red}{4 \pi}} = \frac{1}{2}$