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Thread: some math problems

  1. #1 some math problems 
    Forum Freshman coolaak's Avatar
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    Aug 2006
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    Michigan
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    hi just needed some help...

    1. lim cos x + 1
    x-->pi -----------
    x - pi



    2. find the derivative of
    F(x) = x^1/x


    3. suppose y is a function of x determined by e^xy = y. find y(0) and y'(0)

    i got these wrong on my test and have no idea on how to do them... thx guys


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  3. #2  
    Forum Professor river_rat's Avatar
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    Hints:

    1. Use L'hopitals rule

    2. let y = x^(1/x), then log(y) = log(x)/x. Then use the chain rule (i.e. implicit derivatives)

    3. Finding y(0) is easy. To find y'(0) use implicit derivatives again.

    Hope that puts you on the right track


    As is often the case with technical subjects we are presented with an unfortunate choice: an explanation that is accurate but incomprehensible, or comprehensible but wrong.
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