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.

Printable View

- Aug 15th 2008, 12:17 AMFlayTrigonometric Equations
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. - Aug 15th 2008, 12:24 AMProve It
- Aug 15th 2008, 12:28 AMChris L T521
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 - Aug 15th 2008, 04:29 PMFlay
Thanks, I understand now. I was making a mistake with my postive and negative signs in the simplification of the first equation.