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Math Help - Proving trig identity

  1. #1
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    Proving trig identity

    Not too sure if this question is right. Prove that:

    \dfrac{\cos{x}}{1-\tan{x}}+\dfrac{\sin{x}}{\cot{x}}=1
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  2. #2
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    To prove this identity take only the LHS and manipulate until you get the RHS.

    \dfrac{\cos{x}}{1-\tan{x}}+\dfrac{\sin{x}}{\cot{x}}

    First make a common denominator

    \dfrac{\cos{x}\cot{x}+\sin{x}(1-\tan{x})}{(1-\tan{x})\cot{x}}

    Now do some simplifying
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  3. #3
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    Quote Originally Posted by pickslides View Post
    To prove this identity take only the LHS and manipulate until you get the RHS.

    \dfrac{\cos{x}}{1-\tan{x}}+\dfrac{\sin{x}}{\cot{x}}

    First make a common denominator

    \dfrac{\cos{x}\cot{x}+\sin{x}(1-\tan{x})}{(1-\tan{x})\cot{x}}

    Now do some simplifying
    Yes, but the working doesn't work out
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  4. #4
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    Substitute cot(x)=cos(x)/sin(x) and tan(x)=sin(x)/cos(x). Simplify. Now, you have your answer.
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