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Homework Help: New to the forums, trouble with an integral

  1. Feb 3, 2008 #1
    Hello all, I am new to these forums. I'm having trouble with a problem on homework. It seems simple but it is giving me problems.

    It is an indefinite integral: Integral of (Sin(2x))/(Sinx)dx

    Is there a way to use substitution? Help is appreciated.
     
  2. jcsd
  3. Feb 3, 2008 #2
    [tex]\int\frac{\sin{2x}}{\sin x}dx[/tex]

    Use the trig identity.

    [tex]\sin{2x}=2\sin x \cos x[/tex]
     
  4. Feb 3, 2008 #3
    Use the identity:

    [tex]sin(2x) = 2sin(x)cos(x)[/tex]
     
  5. Feb 3, 2008 #4
    roco, that is correct. Obviously a newb, I have no idea how you did that. I'm sure there are stickies somewhere that I need to read.
     
  6. Feb 3, 2008 #5
    Introducing LaTeX Math Typesetting - https://www.physicsforums.com/showthread.php?t=8997

    Enjoy!
     
  7. Feb 3, 2008 #6
    Alright, wow that is simple when you now the identities. Guess i should get to learning those lol thx awvvu
     
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