Now that you have a better understanding of some of the math topics you've recently covered, take some time to think about these questions. then join the discussion and post your answers.

1. why would knowing the pythagorean identity sin^2x+ cos^2x=1 and the sum identities allow you to prove all the other identities you have seen in this lesson?
2. is sine of (sin^-1x)=sin^-1(sinx) an identity? why or why not?
3. how would you explain to someone who has not yet studied trigonometry the difference between an identity and an equation?
4. what questions do you still have about the unit? ask them here, and your classmates may give you the answers you seek.