A power series can be added, differentiated and integrated just like any polynomial.
To determine the coefficients \(c_n\), follow the steps below:
\[\mathrm{f}'(x) = c_1 + 2c_2x + 3c_3x^2 + \dots\]
Therefore, when \(x = 0\), \(c_1 = \mathrm{f}'(0)\)
\[\therefore \mathrm{f}''(0) = 2c_2 \implies c_2 = \frac{\mathrm{f}''(0)}{2}\]
\[\therefore c_n = \frac{\mathrm{f}^{(n)}(0)}{n!} \text{ where}\hspace{0.5em} 0! = 1 \text{ and}\hspace{0.5em} \mathrm{f}^{(0)}(x) = \mathrm{f}(x)\]
Then \[\mathrm{f}(x) = \mathrm{f}(0) + \frac{\mathrm{f}'(0)}{1!}x + \frac{\mathrm{f}''(0)}{2!}x^2 + \dots + \frac{\mathrm{f}^{(n)}(0)}{n!}x^n + \dots\]
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