Question

What is the amplitude, period and phase shift for `y = 4cos(pix)`?

Answer 1

Amplitude

This is described by the a parameter, or the number directly to the left of the sine or cos, in this case `4`.

Period

The period is given by `(2pi)/b`, where `y = acos(b(x - c)) + d`.

Thus the period is

`(2pi)/pi = 2`

Phase Shift

There is no phase shift because `c = 0`.

Hopefully this helps!