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Homework Help: How do I solve this?

  1. Jun 16, 2010 #1

    majormuss

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    Gold Member

    1. The problem statement, all variables and given/known data
    How do I solve this trig question?
    cot(Arctan (-√(5)/2))

    2. Relevant equations
    The usual equation I know of which is easy o identify on the Unit circle is √3/2. I don't know how to approach this one..


    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Jun 16, 2010 #2

    HallsofIvy

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    Science Advisor

    You do know that cot(x)= 1/tan(x) don't you? So cot(Arctan (-√(5)/2))= 1/tan(Arctan (-√(5)/2)).

    And what do you think tan(Arctan (-√(5)/2)) is?
     
    Last edited by a moderator: Jun 16, 2010
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