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Newton - Raphson question watch

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    Find all solutions using the Newton Raphson method correct to 4dp of

    5x + ln(x)=10,000

    Intuitively I thought one of my solutions should be around 2000. However, my working out alludes to something completely different and I cant quite see where I've gone wrong. I'll post my working out next ...
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    (Original post by ElDonCorleone)
    ...
    x_2 = 2 - \dfrac{5(2)+\ln(2)-10000}{5+\frac{1}{2}}

    You forgot the 10000
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    i) make it equal zero:

    5x + ln(x) - 10000 = 0

    f(x) = 5x + ln(x) - 10000

    f'(x) = 5 + 1/x

    then put these together...

    xn+1 = xn - f(xn)/f'(xn)
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    (Original post by RDKGames)
    x_2 = 2 - \dfrac{5(2)+\ln(2)-10000}{5+\frac{1}{2}}

    You forgot the 10000
    Ahh so trivial, thanks!
 
 
 
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