You can derive the double angle identities from these, use .
Also, to find to use in the formulas use the facts and to determine the sign.
Given that and
Find the exact value of
I was absent this day in class and am not sure about where to start with this problem. I obviously know that you won't do them all, and I don't expect you to or else I'd never learn! But guidance on how to do find and possibly one of the double angle ones would be greatly appreciated.
Could you clarify how to do the double angle ones please? As for the cos u i got this was by recognizing that sin is opposite/hypotenuse and then i put the numbers in a triangle and found the adjacent side using Pythagorean theorem and found the side to be 24 and cos is adjacent/hypotenuse so that's how i got that part.