Expert: Abe Mantell - 1/2/2007

Question
Please help me!!

X is between 0 degrees and 360 degrees (meaning show answer in degrees??)
3sin(x + 20) degrees = -1

3sin(x + 20)= -1
---I divided both sides by 3---
sin(x+20)= -1/3
Now what? I think that I need to find a reference angle or something like that...

Would you show me exactly what to do step-by-step? however, any help that you can offer would be GREATLY appreciated. Thank you in advance for your time.

Answer
Hello Christie,
Now take the inverse sine (arcsin) to get
x+20=-19.47 degrees (approximately

This tells us the reference angle is 19.47, with
sine negative, we have an angles in the 3rd and 4th
quadrants.  Thus, x+20 is about 180+19.47 OR 360-19.47
==> x = 179.47 OR 320.53 degrees.

OK, do you understand?

BTW: Someone else just asked me THE EXACT SAME QUESTION!
    Maybe someone from your class??  What class is this for?

TTYL, Abe