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How does one go about integrating:

$$\int\sqrt{a + x^3}dx$$

Wolframalpha seems to be giving a result that seems slightly too elaborate.

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    $\begingroup$ For $a\ne 0$, there probably is no antiderivative expressible in terms of "elementary" functions. Presumably Alpha used elliptic functions in its answer. $\endgroup$ – André Nicolas Dec 3 '12 at 2:32
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why not use u-substitution? u = a+x^3 then du=3x^2 dx. Should be a good start.

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  • $\begingroup$ This does not suffice, since we do not have a promising way of rewriting the integral in terms of $u$. (Edited for technical accuracy due to DonAntonio's comment.) $\endgroup$ – 000 Dec 3 '12 at 2:45
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    $\begingroup$ Well, it doesn't look very promising, does it? Just take into account that $$dx=\frac{1}{3x^2}du=\frac{du}{3(u-a)^{2/3}}\,...$$ $\endgroup$ – DonAntonio Dec 3 '12 at 2:46

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