Question

Write an equation of the cosine function with amplitude pi/2 and period 3

Answer 1

Answer:

$y = \frac{\pi}{2}cos(\frac{2\pi}{3}x)$

Step-by-step explanation:

Given

$Amplitude = \frac{\pi}{2}$

$Period = 3$

Required

Write the equivalent cosine function

The general formula is:

$y = acos(bx)$

Where

$amplitude = |a|$

$period = \frac{2\pi}{b}$

Substitute $\frac{\pi}{2}$ for amplitude in $amplitude = |a|$

$|a| = \frac{\pi}{2}$

$a = \frac{\pi}{2}$

Substitute 3 for period in $period = \frac{2\pi}{b}$

$\frac{2\pi}{b} = 3$

Multiply both sides by b

$2\pi = 3b$

Divide through by 3

$b = \frac{2\pi}{3}$

Hence;

$y = acos(bx)$ becomes

$y = \frac{\pi}{2}cos(\frac{2\pi}{3}x)$