Answer
1. $sin390^\circ= \frac{1}{2}$.
2. $cos390^\circ= \frac{\sqrt 3}{2}$.
3. $tan390^\circ= \frac{\sqrt 3}{3}$.
4. $cot390^\circ= \sqrt 3$.
5. $sec390^\circ= \frac{2\sqrt 3}{3}$.
6. $csc390^\circ= 2$.
Work Step by Step
1. $sin390^\circ=sin(360+30)^\circ=sin30^\circ=\frac{1}{2}$.
2. $cos390^\circ=cos(360+30)^\circ=cos30^\circ=\frac{\sqrt 3}{2}$.
3. $tan390^\circ=tan(360+30)^\circ=tan30^\circ=\frac{\sqrt 3}{3}$.
4. $cot390^\circ=\frac{1}{tan390^\circ}=\sqrt 3$.
5. $sec390^\circ=\frac{1}{cos390^\circ}=\frac{2\sqrt 3}{3}$.
6. $csc390^\circ=\frac{1}{sin390^\circ}=2$.
