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Homework Help: Differentiate w.r.t x?

  1. Jun 14, 2010 #1
    1. The problem statement, all variables and given/known data

    1) ln { (x^2+x+1) / ( x^2-x+1) } here ln = natural log
    2) x^2+x^(2y)=c here c=constant


    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Jun 14, 2010 #2

    Mark44

    Staff: Mentor

    Show us your attempt at a solution.
     
  4. Jun 14, 2010 #3
    My attempt at 2)

    x^2+x^(2y)=c

    x^2+2ylnx=c

    diff wrt x

    2+(2lnx+1/x.2y.y')=0

    1/x.2y.y'=-2-2lnx

    y'= -2(lnx+1)x / 2y

    is this correct and i can't understand the question no. one and how to start it's differentiation.
     
  5. Jun 14, 2010 #4

    Mark44

    Staff: Mentor

    x2y [itex]\neq[/itex] 2y ln(x).

    You can write x2y as (eln(x))2y = e2y ln(x), and then differentiate.

    For #1, ln(a/b) = ln(a) - ln(b). Use that property of logs before trying to differentiate.
     
  6. Jun 14, 2010 #5
    Thank u very much.....it really helps
     
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