Thank You Vice President
New member
- Joined
- Oct 7, 2020
- Messages
- 4
Because cosine is an even function \(\cos(x)=\cos(-x)\).What is the cos(30)? What is the cos(-30)? How about cos(60) and cos(-60)?
See if a pattern begins to emerge.
Yes, that was the "easier way" I would have told you if your method had been to use angle subtraction identities!I found out how to do it, it was an even and odd function. Cosine(-theta)=cosine(+theta), so its -15/22