Trigonometric Functions

1. sec^2(x)=tan^2(x)+1

2. cos^2(x)+sin^2(x)=1

3. csc(x)=1/sin(x)

4. cos(2x)=1-sin^2(x)

5. cos(2x)=2cos^2(x)-1

6. tan(x)=sin(x)/cos(x)

6.1. sin(x)/cos(x)

7. cot(x)=1/tan(x)

8. sin(2x)=2sin(x)cos(x)

9. csc^2(x)=1+cot^2(x)

10. sec(x)=1/cos(x)