I'm not sure how to tackle this question, can anyone help me out? It asks;
a) Show that .
b) Hence find the value of in simplest exact form.
For part a, focus on the left side of the equation.
First multiply the numerator and denominator by
Note that and
Thus, the identity becomes . We have proven the identity. Does this make sense?
For part (b), note that
Apply the half angle identity , where .
Does this make sense?
--Chris