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Math Help - i need help proving the indentity

  1. #1
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    i need help proving the indentity

    (1/1-sinx)-(1/1+sinx)=2sectan
    i got stumped on this one
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  2. #2
    MHF Contributor alexmahone's Avatar
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    Quote Originally Posted by valvan View Post
    (1/1-sinx)-(1/1+sinx)=2sectan
    i got stumped on this one
    \frac{1}{1-sinx}-\frac{1}{1+sinx}

    = \frac{2sinx}{1-sin^2x}

    = \frac{2sinx}{cos^2x}

    = 2\frac{1}{cosx}\frac{sinx}{cosx}

    = 2secxtanx
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  3. #3
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    can you explain further how you got to
    =
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  4. #4
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    Quote Originally Posted by valvan View Post
    can you explain further how you got to
    =
    HI

    \frac{1}{1-sinx}-\frac{1}{1+sinx}

    Just combine the fractions .

    \frac{1+\sin x}{(1-\sin x)(1+\sin x)}-\frac{1-\sin x}{(1+\sin x)(1-\sin x)}
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  5. #5
    Senior Member pacman's Avatar
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    = Numerator/Denomenator

    Numerator = (1 + sin x) - (1 - sin x) = 1 + sin x - 1 + sin x = ?
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