I'm working on a problem.
The problem is boxed in Blue. Ignore the right side boxed in green, it's unreleated. Inside the blue box, I have highlighted in green where my error is when solving this problem.
This problem is from a website, and I'm a little confused, as to why my answer (boxed in red) is wrong. I've used Desmos.com and my answer is indeed wrong. It seems that I'm not understanding how the + and - signs are working? to get the first part of my answer inside of the error box I used the special angle identities.
Thanks in advance for any input.