I've been having some trouble with some trig problems. It would be great if someone could help me to do them. I'm not very sure how to put in symbols such as pie, etc. so I apologize in advance for having to write it out.

*Using a sum/difference formula, find the exact value of tan pie/12.

*Simplify/evaluate to find the exact value of 1-2sinsquared15 degrees.

*Verify (sinx-cosx)squared= 1-sin2x.

*Find solutions for 2cos squared x+sin squared x=2cosx if X is between 0 degrees and 360 degrees.

* Find solutions for 2 sin squared x+5sinx=-3 if x is between 0 degrees and 360 degrees.

Thank you!