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Homework Help: Theta question

  1. Oct 12, 2008 #1
    1. The problem statement, all variables and given/known data

    If tan^-1 (3/5) = Θ , what is csc^-1 (cotanΘ)

    i don't get the question
  2. jcsd
  3. Oct 12, 2008 #2


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    Try writing everything in terms of sines and cosines.
  4. Oct 12, 2008 #3


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    Another way to do this is to draw a triangle. Since tangent= "opposite leg over near leg", draw a right triangle havine legs of length 3 and 4, with the leg of length 3 opposite angle [itex]\theta[/itex]. Find the length of the hypotenuse using the the Pythagorean theorem (if it isn't obvious) and then it should be simple to find cotan([itex]\theta[/itex]).

    Another, rather obvious, way to do this is to use a calculator!
  5. Oct 13, 2008 #4
    tan^-1 (3/5) = Θ , what is csc^-1 (cotanΘ)

    If tan^-1(3/5) = Θ then tan(Θ) = 3/5

    csc^-1(cot(Θ)) = csc^-1(1/tan(Θ)) = csc^-1(1/3/5) = csc^-1(5/3)

    You should be able to take it from there.
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