K, so my teacher presented a set of problems and it is basically impossible to get all of them right (it was a competition to see who could do the most). There were a ton of problems and after going to class I still don't understand how to do some of them.
Disprove the following identity by counterexample:
Everything that I plug in says that this isn't an identity. What am I doing wrong?
Prove the following identities:
I spent 2 hours trying to prove this, and I am coming with a nothing.
And the third one
Solve the following:
I have a bunch of these that I didn't get right that I don't understand, but these 3 are really bugging me. I already know the answers, so I mostly care about how to get that answer because so far I haven't been able to figure it out. Any help will be great!!!