Don't you have a textbook that you could learn from? If not, there are plenty of websites that you could reference.

None of these make sense. Sine, cosine, and tangent arefunctions. They each require an input. One cannot evaluate "sin" by itself, you need to specify what you are taking the sine of. When you wrote sin^2 Did you mean to write ? Because even then I can't figure out how to interpret that first identity. , for example.