Appendix B - Trigonometry Review - Exercise Set B - Page A23: 3

$$3a)\,\,{12^ \circ },\,\,\,3b){\left( {\frac{{270}}{\pi }} \right)^ \circ },\,\,\,\,3c){288^ \circ },\,\,\,\,\,3d){540^ \circ }$$

$$\eqalign{ & 3\left( {\text{a}} \right)\,\,\,\frac{\pi }{{15}} \cr & {\text{Express the angle in degrees}} \cr & \frac{\pi }{{15}} = \,\,\frac{\pi }{{15}}{\left( {\frac{{180}}{\pi }} \right)^ \circ } \cr & \,\,\,\,\,\,\, = \,\,{\left( {\frac{{180}}{{15}}} \right)^ \circ } \cr & \,\,\,\,\,\,\, = \,{12^ \circ } \cr & \cr & 3\left( {\text{b}} \right)\,\,1.5 \cr & {\text{Express the angle in degrees}} \cr & 1.5 = \,\,1.5{\left( {\frac{{180}}{\pi }} \right)^ \circ } \cr & \,\,\,\,\,\,\, = \,{\left( {\frac{{270}}{\pi }} \right)^ \circ } \cr & \cr & 3\left( {\text{c}} \right)\,\,\frac{{8\pi }}{5} \cr & {\text{Express the angle in degrees}} \cr & \frac{{8\pi }}{5} = \,\,\frac{{8\pi }}{5}{\left( {\frac{{180}}{\pi }} \right)^ \circ } \cr & \,\,\,\,\,\,\, = \,{\left( {\frac{{1440}}{5}} \right)^ \circ } \cr & \,\,\,\,\,\,\, = \,{288^ \circ } \cr & \cr & 3\left( {\text{d}} \right)\,\,3\pi \cr & {\text{Express the angle in degrees}} \cr & 3\pi = \,\,3\pi {\left( {\frac{{180}}{\pi }} \right)^ \circ } \cr & \,\,\,\,\,\,\, = \,{\left( {3 \cdot 180} \right)^ \circ } \cr & \,\,\,\,\,\,\, = {540^ \circ } \cr} $$