Solve questions 15,16,17, and 18. will give ! show minimal work!

15. The terminal side of intercepted the unit circle at:

(0,-1).

This implies that:

This implies that:

16) We have that: .

We illustrate this on the right triangle and apply the Pythagoras Theorem as follows:

Using the mnemonics SOH-CAH-TOAH, we have:

17. We want to verify that:

Verifying from the LHS

Recall that from the Pythagorean identity:

18.  We have:

When , we have

When ,

We can see this is not defined for all real values of x.

21.4 i did it already for s1

step-by-step explanation: