# What is the period and amplitude for z = 5cos(u/6)+11?

This function has a period of $12 \pi$ and amplitude 10.
$f \left(x\right) = a \cdot \cos \left(b x\right) + c$ then its period is $P = \frac{2 \pi}{a}$ and its amplitude is $2 a$ because the values of the function change from $- a + c$ to $a + c$.