Advanced Math/trig

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Expert: Jack Cheng - 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...

Can you please show exactly what i need to do step-by-step? However, any help you can offer would be GREATLY appreciated. Thank you in advance for your time.

Answer
Hi Christie,

I don't have a calculator, so I can't finish the problem for you. But here it is:

sin(x+20)= -1/3
   x+20 = arcsin(-1/3)
      x = arcsin(-1/3) - 20

(Arcsin is the same as the inverse sin: sin^(-1).)

I hope this helps,
Jack

P.S. Do you happen to know someone by the name of Jon? He asked the very same question with the very same wording. What a coincidence :)

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Jack Cheng

Expertise

I can answer most questions in Math up to single-variable Calculus, including infinite series. I like to think very much, so questions with a lot of twists and turns are highly welcomed! Mathematical questions related to computer science are also highly welcomed! I can also answer some basic questions in discrete mathematics (logics, sets, some algorithms, basic number theory). I am also studying physics (mechanics in particluar), so I am willing to answer some questions relating to it.

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Majoring in Mathematics.

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I am sophomore/junior status in college working towards bachelor's degrees in Computer Science and Mathematics.

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