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Evaluate the integral of earctan x / (1+x2)3/2

Evaluate the following integral

    \[ \int \frac{e^{\arctan x}}{(1+x^2)^{\frac{3}{2}}} \, dx. \]


From the previous exercise (Section 6.22, Exercise #40) we know

    \[ \int \frac{e^{arctan x}}{(1+x^2)^{\frac{3}{2}}} \, dx = \int \frac{x e^{\arctan x}}{(1+x^2)^{\frac{3}{2}}} \, dx + \frac{e^{\arctan x}}{\sqrt{1+x^2}}. \]

From the same exercise we also know that

    \[ \int \frac{x e^{\arctan x}}{(1+x^2)^{\frac{3}{2}}} \, dx = \frac{(x-1)e^{\arctan x}}{2 \sqrt{1+x^2}}. \]

Therefore, we have

    \begin{align*}  \int \frac{e^{\arctan x}}{(1+x^2)^{\frac{3}{2}}} \, dx &= \frac{(x-1)e^{\arctan x} + 2e^{\arctan x}}{2 \sqrt{1+x^2}} + C \\[10pt]  &= \frac{(x+1)e^{\arctan x}}{2\sqrt{1+x^2}} + C. \end{align*}

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