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Math Help - Consider the equation...

  1. #1
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    Consider the equation...

    I need help revising this. Not sure what it's called and would love help on solving and naming what it is so that i can google/youtube about it and start revising (hopefully).

    Consider the equation x3 - 3x2 + 2 = 0.

    1. By presenting a suitable graph, state how many real solutions there are to this equation, and define them very roughly from the graph (to about 1 dp).



    1. Perform 5 iterations of the Newton-Raphson method by hand, to find the solution of the above equation x3 - 3x2 + 2 = 0 starting from the point x0. Complete the following table, using 4 decimal places of accuracy for each entry in the table.


    (n) iterations xn f(xn) (df(xn)) / dx ( |xn - xn-1 | ) / xn
    0 2.5
    1
    2
    3
    4
    5
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  2. #2
    MHF Contributor Siron's Avatar
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    Re: Consider the equation...

    Can you show what you have tried already? Have you tried to make a graph? What about the table?
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  3. #3
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    Re: Consider the equation...

    Do the first as instructed, i.e. plot points on an x-y grid for a range of values of x, (where the corresponding value of y for each point is the output from the equation for that x value), join the points in a continuous curve and see where it crosses the x-axis (because the output is zero).

    Then google 'Newton-Raphson' for the formula you need for the second exercise.

    PS: missed Siron's post.
    Last edited by tom@ballooncalculus; March 13th 2012 at 05:13 AM.
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  4. #4
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    Re: Consider the equation...

    How do i plot on the grid? Are there youtube videos i can search for that show it?
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  5. #5
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    Re: Consider the equation...

    I think i need to take a step back and learn a little basic math... Learning how to plot and other things as i go along. I have plenty of time to work on this and plenty of time on my hands as well... So hopefully all goes well.

    Thanks a lot for the help i'll be back to this question once i've built a bit more foundation over the next day or so.
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