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Homework Help: MatLab help with e^x

  1. Sep 20, 2010 #1
    1. The problem statement, all variables and given/known data

    Plot e^x for -10 to 10 using a Taylor series about 0
    find the error between the nth term and the actual value of e^-10 and e^10

    plot sin(4*theta) using a 2 term expansion, a 4 term expansion and a 10 term expansion and constrast it with the plot of sin(4*theta)

    3. The attempt at a solution

    This is the first time I have ever opened MatLab and tried to do any sort of math programming. I suppose I need help in the logic of it or trying to trace what I am doing.

    So far I have:

    Code (Text):

    %This will compute the Taylor Series expansion of e^x for a user defined
    %x value for the number of terms required by the user.  It will do this about the point
    %a=0.  The result of the
    %nth term will be compared to the computer generated value of e^x

    x = input ('Enter a value for x:'); % user input of which value to use for x
    i = input ('Enter the non-zero number of terms for this Taylor Series expansion:'); %user input of number of terms to use

    % g_n: the nth term in Taylor Series

    k=1;    % initialize k

    g_n=x^(k-1)/factorial(k-1);   % begin with the first term


    while  i>k; % let index increase until number of desired terms reached
        k=k+1;  % increase index by 1
        g=g+g_n; %add the next term in the series  

    I changed my code to what is listed above and it seemed to help entirely.
    Last edited: Sep 20, 2010
  2. jcsd
  3. Sep 20, 2010 #2
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