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Math Help - Proving an identity

  1. #1
    Junior Member
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    Proving an identity

    I am having trouble proving the following:

    cscx + secx = cotx + tanx
    sinx + cosx
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  2. #2
    Senior Member
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    \frac {\csc x+\sec x}{\sin x+\cos x}=\frac {\frac 1{\sin x}+\frac 1{\cos x}}{\sin x+\cos x}=\frac {\frac {\cos x+\sin x}{\sin x\cos x}}{\sin x+\cos x}=\frac 1{\sin x\cos x}=\frac {\cos x}{\sin x}+\frac {\sin x}{\cos x}
    using the identity \sin^2x+\cos^2x=1 (in the last step).
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  3. #3
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    Ok...

    How did you get:

    cosx+sinx = 1
    sinxcosx
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  4. #4
    Junior Member
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    I figured out how you got all the way to:

    1/sinxcosx

    but how did you get the last part?
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  5. #5
    Junior Member
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    Nov 2008
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    Thank you...

    I figured it out...

    Thank you so much!
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