We note that the error in Simpson’s rule depends on (b − a)
5, while the error
in the midpoint rule and trapezoid rule depend on (b − a)
3. This means that
the error in Simpson’s rule goes to zero much more quickly than for the other
two methods when the width of the interval [a,b] is reduced. More precisely, a
reduction of h by a factor of 2 will reduce the error by a factor of 32.
As for the other two methods the constant 49/2880 is not best possible; it can
be reduced to 1/2880 by using other techniques.