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\begin{equation}
 \begin{split}
  I & = I(x_{0} + 2h)\\
& = I(x_{0}) + 2hI^\prime (x_{0}) + 2h^2 I^{\prime\prime} (x_{0}) + \frac{4}{3}h^3 I^{\prime\prime\prime}(x_{0}) + \frac{2}{3}h^4 I^4 (x_{0}) + \frac{4}{15}h^5 I^5 (x_{0}) + \dots \\
& =  2hf(x_{0}) + 2h^2 f^\prime (x_{0}) + \frac{4}{3}h^3 f^{\prime\prime}(x_{0}) + \frac{2}{3}h^4 f^{\prime\prime\prime}(x_{0}) + \frac{4}{15}h^5 f^{(4)}(x_{0}) + \dots 
\end{split} 
\end{equation}
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