How many points are necessary to calculate $\int_2^6\ln(x)dx$ using Simpson's rule with error $\le 5*10^{-4}$?

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How many points of integration are necessary to calculate the integral

$$\int_2^6\ln(x)dx$$

using Simpson's rule such that the absolute error of integration is lesser or equal to $5*10^{-4}$, knowing that the values for $\ln(x)$ have 7 significant digits?

$$E(f) = -\frac{h^4(b-a)}{180}f^{(4)}(\eta)$$ $$h = \frac{b-a}{N}$$ where N = number of intervals in between points, which should me even for Simpson's Rule.


What I tried to do:

$$h = \frac{6-2}{N} = 4/N \\ E(f) = -\frac{4^5}{N^4}*1/180*f^{(4)}(\eta) \\ f^{(4)} = -6x^{-4} \\ |E(f)| \le 5*10^{-4} \Leftrightarrow \\ |\frac{4^5}{180N^4}|\max_{6,2}|-6x^{-4}| \le 5*10^{-4} \Leftrightarrow \\ N = 0.12374 \approx 1$$

This solution doesn't make a whole lot of sense. Help?