Phase angle
In a function such as sine or cosine, we could also have a translation of the form:
\(y = \sin (x - a)^\circ\) where \(a\) is called the phase angle.
This is when the graph of the function has been shifted to the left or right by \(a\) degrees.
If you have:
- \(\sin {(x - a)^ \circ }\), then the graph has been moved to the right
- \(\sin {(x + a)^ \circ }\), then the graph has been moved to the left
Question
Sketch the graph of \(y = \sin (x - 10)^\circ\)
As \(a = 10^\circ\), this means that the sine graph has been shifted to the right by 10˚.
The graph looks like:
