Figure A-7.9(a) provides a graph of one period of the sine function wherein the horizontal axis is scaled in degrees, rather than in radians.

To obtain such a graph, apply the plot command, with range $x\in \left[0\,360\right]$, to $\sin \left(\mathrm{\π} x\/180\right)$.

Alternatively, let Maple change the argument of the sine function via a call to the Units package, as explained below.

Tools≻Load Package: Units

Write $\sin \left(x\right)$, but after the $x$ leave a space and invoke the generic unit template from the Units (FPS) palette.

Change the placeholder unit to degrees.

Context Panel: Evaluate and Display Inline