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Definite Integration with Upper bound as another integral.

  1. Apr 21, 2010 #1
    Hi guys, just got owned by my calc prof with a final exam question. Very very weird. Attempted it and different approach apparently gets u different answers. I have no idea what's going on..

    View attachment Exam question.doc
    I have attached the question as a word document. Too much integration to type and I cannot really use the Latex Reference well. Equation Builder in Microsoft Word is more helpful for me.

    I have noticed too that the upper bound integral forms a non-elementary function thus I am unsure if my methods are right. The prof obviously wants us to really think hard. I sure hope the 1st approach of finding the general form first is right. The 2nd method of direct substitution from the initial start seems weird.

    Thanks everyone for your help!
  2. jcsd
  3. Apr 21, 2010 #2


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    Your first method is correct. Your second method fails because you are essentially claiming that [itex]G'(0)=\frac{d}{dy}G(0)[/itex], which is nonsense. You must first differentiate and then plug in the point at which you want to find the derivative; doing things the other way around will always give you zero, regardless of the function you are differentiating.
  4. Apr 21, 2010 #3
    YAY! THANKS! :D:D:D now i have ease of mind about my exam! :D:D:D thanks!

    yeah i realised that too which doesnt seem to be making sense. the prof is one hell of a tricky guy. he loves doing stuff like that.

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