How do you graph and list the amplitude, period, phase shift for y=3cos(3x)+3?

1 Answer
Feb 2, 2018

The amplitude of the function is 3, the period is 2π3, and the phase shift is 0.

Explanation:

For the general cos wave

y=Acos(B(xC))+D,

the wave is amplified by |A|, horizontally compressed by B, translated right C (phase shift), and translated up D.

Here are the values of our equation:

y=3cos(3x)+3

|A|=amplitude=3

B=compression=3

C=phase shift=0

D=vertical shift=3

To find our period, we take 2π (the period of the normal sinusoidal wave) and divide it by our B value:

period=2πB=2π3

Finally, the phase shift is our C value, which in this case is 0 (because it is not present).