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Homework Help: Newton's Method

  1. Apr 30, 2007 #1
    1. The problem statement, all variables and given/known data
    Identify the formula

    xn+1 = -2xn + 3yxn^(2/3)

    as the Newton's method for a certain function. Here y is a fixed constant. What is the limit of xn?


    2. Relevant equations
    Newton's method?:

    xn+1 = xn - f(xn)/f'(xn)


    3. The attempt at a solution
    I don't know how to begin.

    Thanks in advance!
     
  2. jcsd
  3. Apr 30, 2007 #2
    1st step- Newton's method gives

    x_n-x_{n-1}=f(x_n)/f'(x_n)

    So rearrange your equation to get f(x_n)/f'(x_n). Then think.
     
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