Question

What is the graph of `y=cos(x-pi/4)`?

Answer 1

The same as graph of `cos(x)` but shifts all the point `pi/4` radians to the right.

Explanation:

The expression is actually saying:

Trace the curve of `cos(c)` backward until you reached the point on the x-axis of `x-pi/4` radians and note the value. Now move back to the point on the x-axis of `x` and plot the value you would have noted at `x-pi/4`.

My graphing package does not work in radians so I was forced to use degrees. `pi " radians" = 180^0 " so "pi/4 = 45^0`

The pink plot is the blue dotted plot transformed `pi/4` radians to the right. In other words it is `cos(x-pi/4)`