# How do you find the amplitude and period of a function y = -2/4 cos (7/2)x?

Feb 27, 2016

amplitude$= \frac{1}{2} , p e r i o d = \frac{4 \pi}{7}$

#### Explanation:

The standard form of cos function is :

y = acos(bx + c )

where $| a | \text{is amplitude" , period = (2pi)/b " or } {360}^{\circ} / b$ and c is phase shift.

here $y = - \frac{1}{2} \cos \left(\frac{7}{2}\right) x$

$\Rightarrow | a | = \frac{1}{2} \text{ and period } = \frac{2 \pi}{\frac{7}{2}} = \frac{4 \pi}{7}$