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Homework Help: Immediate help needed (limits)

  1. Feb 3, 2005 #1
    Immediate help needed (limits)!!

    hi everyone....I need an answer for this limit question by friday(feb/04/2005)....ok the question is to find the limit as "x" approaches 1 for the equation...sqare root "x" subtract "x" sqared divide by 1 subtract sqare root "x".....sorry guys but i dont know how to use the codes yet...anyways....I used the calculator to find out that the limit is three but I am stuck in doing the algebra. I tried to rationalize both the denominator and the nemoritor and basically came up with (x-4)(1+sqaure root "x")/(1-x)(square root "x" +x^2)...I also multiplied them but couldnt cancel out anything....any help would be greatly appreaciated. :cool:
     
  2. jcsd
  3. Feb 3, 2005 #2

    Curious3141

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    Homework Helper

    Substitute [tex]u = \sqrt{x}[/tex] and express everything in terms of u.

    For the resulting expression, factorise the numerator completely. Cancel the common factor(s) between numerator and denominator and you get an expression in u that has an obvious limit as u tends to 1.
     
    Last edited: Feb 3, 2005
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