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    I've just been entirely defeated by an NM past paper question (Jan 2007 Q7).

    I've found the wrong Simpson's estimates. Rather than finding them for h = 0.5 and h = 0.25, I have seemingly found them for h = 0.25 and h = 0.125 (respectively) instead.

    Having checked my textbook and the specification to work out why, they contradict each other. The textbook says that Simpson's rule with n strips, S_n is given by

    S_n = \frac{2M_n + T_n}{3}

    Where T_n and M_n are the trapezium and midpoint estimates.

    The specification however says that

    S_{2n} = \frac{2M_n + T_n}{3}

    Where M_n and T_n are defined as before and S_{2n} is the Simpson's estimate with 2n strips.

    So what is the strip number in Simpson's Rule? Is it the number of strips used in the Midpoint and Trapezium rule to get that Simpson's estimate, or is it twice that number? The latter would give me the right answer but the former is what I was taught.
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    (Original post by 16Characters....)
    I've just been entirely defeated by an NM past paper question (Jan 2007 Q7).

    I've found the wrong Simpson's estimates. Rather than finding them for h = 0.5 and h = 0.25, I have seemingly found them for h = 0.25 and h = 0.125 (respectively) instead.

    Having checked my textbook and the specification to work out why, they contradict each other. The textbook says that Simpson's rule with n strips, S_n is given by

    S_n = \frac{2M_n + T_n}{3}

    Where T_n and M_n are the trapezium and midpoint estimates.

    The specification however says that

    S_{2n} = \frac{2M_n + T_n}{3}

    Where M_n and T_n are defined as before and S_{2n} is the Simpson's estimate with 2n strips.

    So what is the strip number in Simpson's Rule? Is it the number of strips used in the Midpoint and Trapezium rule to get that Simpson's estimate, or is it twice that number? The latter would give me the right answer but the former is what I was taught.
    the former is correct. the mark scheme must be wrong
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    (Original post by 16Characters....)
    ...
    (Original post by HapaxOromenon2)
    the former is correct. the mark scheme must be wrong
    I'm confused as well now: this, this and this say it is S_{2n} and the explanation given in the latter link makes complete sense.
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    (Original post by HapaxOromenon2)
    the former is correct. the mark scheme must be wrong
    (Original post by Zacken)
    I'm confused as well now: this, this and this say it is S_{2n} and the explanation given in the latter link makes complete sense.
    Thanks for the help.
 
 
 
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