# How do you graph f(x) = 4 cos(x - pi/2 )?

Jul 31, 2018

See a sine wave and details.

#### Explanation:

$y = 4 \cos \left(x - \frac{\pi}{2}\right) = 4 \cos \left(\frac{\pi}{2} - x\right)$

$= 4 \sin x \in 4 \left[- 1 , 1\right] = \left[- 4 , 4\right]$

The amplitude of this sine wave is 4 and the period is $2 \pi$.

See wave, for one period, $x \in \left[- \pi , \pi\right]$:
graph{(y - 4 sin x)(y^2-16)(x^2-(pi)^2)=0[-6.4 6.4 -4.2 4.2]}