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Help with sets and some trig

  1. Sep 14, 2008 #1
    Hi, I just have three question and I'm wondering how to solve them.

    The first one is a sets question and it is literally infuriating trying to even contemplate it. I've asked many other people how to solve and no one knows how. I was hoping there would be a few geniuses that solve it here

    The other 2 are just trig questions. I have a feeling at the back of my head that I knew how to solve them, but that's it.

    Attached Files:

  2. jcsd
  3. Sep 15, 2008 #2


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    Homework Helper

    Hi guynoone! :smile:

    Why couldn't you just type them out? :confused:

    To show that sin3x/(1 + cos3x) = tyan(3x/2), just write sin3x and cos3x in terms of functons of 3x/2. :smile:
  4. Sep 15, 2008 #3
    I hate looking for the correct symbols. I also wanted to test out the new scanner :)

    Sorry, my mind's a bit fuzzy. What happens to that +1 then?
  5. Sep 15, 2008 #4


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    Science Advisor

    Why don't you try what he suggested and then see what happens?
    sin(3x)= sin(2(3x/2) and cos(3x)= cos(2(3x/2) so tiny-tim is suggesting you use the double angle formulas.
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