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Math Help - Trig Identities

  1. #1
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    Trig Identities

    Hello just got a couple problems I'm stuck on. Seeking some help.

    csc^-1x = sin^-1 (1/x)

    and

    sec^-1(x) = cos^-1 (1/x)
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  2. #2
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    Let y = \sin^{-1} x.

    So:
    \sin y = x
    \frac{1}{\sin y} = \frac{1}{x}
    \csc y = \frac{1}{x}
    y = \csc^{-1} \left(\frac{1}{x}\right)
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  3. #3
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    Would the second question have the same set up as the previous.

    Show that the following identity is true
    sec-1x = cos-1 (1/x)

    let y= cos^-1

    cosy=x

    1/cosy=1/x

    secy=1/x

    y= sec^-1 (1/x)

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  4. #4
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    Yep. Don't doubt yourself!
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  5. #5
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    Thanks. I will work on that not doubting myself part as I continue to work through some more of these.
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