Question

How do you graph `y = 1/2cos x`?

Answer 1

If you know how to graph `cos(x)` then just shrink it vertically by `1/2` this would give you the graph of `y=1/2 cos(x)`

Explanation:

Let me take a couple of known values of `cos(x)` which would help you understand what happens to the graph of `cos(x)`.

`cos(0)=1` but for `1/2 cos(0) = 1/2 (1) = 1/2`
Similarly each value of `cos(x)` is halved.

The final graph would be vertically shrunk.