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New calculus problem HELP

  1. Jul 29, 2004 #1
    new calculus problem.. HELP!!

    Hi there... i need a help with this question as soon as possible...

    Find a positive number such that the sum of the number and its reciprocal is as small as possible..?
  2. jcsd
  3. Jul 29, 2004 #2
    Minimize f(x) = x + 1/x.
  4. Jul 29, 2004 #3
    i'm kind of lost here, i need a full answer
  5. Jul 29, 2004 #4
    Well, I'm not going to give it to you... How lost are you exactly? Do you know how to calculate the derivative of x + 1/x?
  6. Jul 29, 2004 #5
    actually, i don't know how you get x + 1/x.. i can calculate its derivative though.. please explain the way the you got x + 1/x..

  7. Jul 29, 2004 #6
    x = a number.
    1/x = that number's reciprocal.

    x + 1/x = a number plus its reciprocal.
  8. Jul 29, 2004 #7
    thanks a lot.. i appreciate your help :)
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