PROVE THE IDENTITY.

?

Do you understand that you're trying to show how one side (or both), can be transformed into the other?

Start by writing the secant term using a fundamental identity for secant:

sec(x) = 1/cos(x)

After you replace sec(x) with 1/cos(x), look at the double-angle identity for sine.

sin(2x) = 2 sin(x) cos(x)

After you replace sin(2x) with 2 sin(x) cos(x), reduce the ratio by canceling common factors.

Questions?

?
 
Top