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A Trig Proof

  1. May 4, 2004 #1
    Yes it is me again. :D Now with a trig problem XD

    I was doing some problems on my homework in math, Trigonometry and I had problems proving this proof:

    1+ cos Ө = csc Ө + cot Ө

    I've worked it out until I simplified the right side to:

    sin Ө
    -----
    1+ cos Ө

    And then I realized that was the half identity of tangent. I can;t make the connnection further to make the proof true. Please help!! Have I simplified it wrong?

    edit: the Ө is supposed to represent theta... but it keeps showing up like a square.. but you know what I mean. :D
     
  2. jcsd
  3. May 4, 2004 #2
    isnt csc = 1/sin and cot = cos/sin?

    if that is so than the RS:
    1/sin + cos/sin
    (1+cos)/sin

    (forgive me for not putting in thetas)
     
  4. May 4, 2004 #3
    Yeah that is what I got, but it's not eqaul to the left side, which is what I am supposed to do.
     
  5. May 4, 2004 #4

    Hurkyl

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    Do you believe the identity is correct?
     
  6. May 5, 2004 #5
    See that's why I am confused. I've checked my work about a million times (maybe 5 or so times :D) and I keep coming up with the same solution. I checked the answer in the book and it says that the proof is true... so either I'm doing something wrong or it's an error in the book. :1
     
  7. May 5, 2004 #6

    Integral

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    There must be a misprint, I did a quick calculation to show that they are equal at some point but certianly not in general
    x..............1+cos(x)...........csc(x)+cot(x)
    0.1.........1.995004165........19.98333055
    0.2.........1.980066578.........9.966644423
    0.3.........1.955336489.........6.616591506
    0.4.........1.921060994.........4.933154876
    0.5.........1.877582562.........3.916317365
    0.6.........1.825335615.........3.232728144
    0.7.........1.764842187.........2.739512159
    0.8.........1.696706709.........2.36522242
    0.9.........1.621609968.........2.070157361
    1............1.540302306.........1.830487722
    1.1.........1.453596121.........1.631041424
    1.2.........1.362357754.........1.461695947
    1.3.........1.267498829.........1.315435692
    1.4.........1.169967143.........1.187241832
    1.5.........1.070737202.........1.073426149
    1.6.........0.970800478.........0.971214601
     
    Last edited: May 5, 2004
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