#469 Working with triangles using trig
#461 Using a Cartesian plane when working with trig ratios
#462 Using special angles
#532 Calculating the biggest possible angle of inclination
#533 Sketching fx = 3cos2x
#534 Simplifying a trig identify to prove LHS=RHS
#551 Dealing with a range of trig questions
#552 Working with trig equations and trig graphs
#553 Using trig when working with a 3D shape
#735 Solving a tricky general solutions question using compound angles