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Math Help - [SOLVED] Trig Function

  1. #1
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    [SOLVED] Trig Function

    Suppose cot = 3 in the 3rd quadrant.

    I know that tan = 1/3 and than both sin and cos are negative, but i can't figure out what the values for them are.

    I tried sin = 1/3cos and then

    cos^2 + 1/9cos^2 = 1

    cos^2 = 8/9

    cos = -2sqrt(2)/3 but then i keep getting the wrong answer. Can someone help me find sin and cos please
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  2. #2
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    Quote Originally Posted by goliath View Post
    Suppose cot = 3 in the 3rd quadrant.

    I know that tan = 1/3 and than both sin and cos are negative, but i can't figure out what the values for them are.

    I tried sin = 1/3cos and then

    cos^2 + 1/9cos^2 = 1

    cos^2 = 8/9

    cos = -2sqrt(2)/3 but then i keep getting the wrong answer. Can someone help me find sin and cos please
    use the identity ...

    \tan^2{x} + 1 = \sec^2{x} = \frac{1}{\cos^2{x}}
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  3. #3
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    Using \tan \theta = \frac{1}{3} you can find the long side of the triangle using pythagora's theorem.

     h^2 = 1^2+3^2

    Then you can find the solutions to the remaining problems.
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