Posted by Edwards on .
1. Show that Sin3 Theta - Cos2 Theta = (1 - Sin Theta)(4Sin^2 Theta + 2Sin Theta - 1).
Without using a calculator, show that Theta = 18 degrees is an exact solution of the equation Sin3 Theta = Cos2 Theta.
Justifying your answer, find the exact values of:
i) Sin18 degrees.
ii) Sin234 degrees.