11 HL: Solving Trigonometric Equations

Yesterday we discussed finding the general solution to a simple trigonometric equation. Try each of the questions below before our next class.

1. Explain how the image shown below illustrates one of the results we discussed in the last class.
   
   Hint

   Two points are shown on the circumference of the unit circle. Colour one red, and the other blue.
2. Find the general solution to the equation $\cos \theta = \frac{1}{2}$, expressing your answers as exact values.
3. Find the general solution to the equation $2\sin^2\theta -5\sin \theta = -2$.