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Numerical differentiation using forward, backward and central finite difference

  1. Feb 2, 2010 #1
    ive been given this question for a uni assignment:

    given the function:

    f (x) = 5(x^1.3) +1.5(7x − 3)+ 3(e^− x) + ln(2.5(x^3))

    find the first derivative at all possible points within the interval [0, 6], with step length h = 1 for:
    forward difference aproximation, backward difference aproximation and central finite difference aproximation.

    having a bit of trouble with the question... pretty sure i know how to do most of it but not sure what to do when x=0 because ln(0) is undefined or -infinity...

    any ideas?

    thanks
     
  2. jcsd
  3. Feb 2, 2010 #2
    Well, it says "for all possible points" which would exclude any points where ln(0) appears.
     
  4. Feb 8, 2010 #3

    LOL I'm guessing you're from brunel :P
    I've figured out how to do the hand calculations but not the matlab part
     
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