Question

How do you graph `y= 0.5cos 4x`?

Answer 1

For a general trigonometric cosine graph of the form `y=Acosbx`, A is the amplitude, ie the maximum displacement from the x-axis, and `(2pi)/b` is the period, where period is the length on the x-axis for a complete cycle.

So in this case, the amplitude is 0,5 and the period is `(2pi)/4=pi/2`

So in `360^@=2pirad,` the graph will make 4 complete cycles, and will hence look as follows :

graph{0.5cos(4x) [-2.5, 2.5, -1.25, 1.25]}