How to evaluate this indefinite integral?

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I arrived on the below integral as part of solving an ODE, but have no clue how to proceed.

$y = \int\frac{e^x}{x^2}dx$

I tried by parts to reduce it to solving

$y = \int\frac{e^x}{x}dx$

I feel like it is a standard integral, but am unable to proceed.

Would appreciate it if someone could tell me how to search for such things on Google.

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The function $\frac{e^x}x$ has no elementary primitive. So, no, it is not a standard integral.

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Two methods to solve integrals with the form $e^x x^{-n} dx$:

  • Either use the power series of the exponential function, then integrate, then sum back

  • Do $n$ integration by parts. As you may have noticed, you reduce the order of the exponent of $x$ by one at each integration by parts.

Also please note that $\int e^x x^{-1}dx$ is called the exponential integral and has no standard writing other than $Ei(x)$.

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The integral $\int \frac{e^x}{x}dx$ cannot be expressed with a finite number of elementary functions.

A closed form requires a special function named Ei$(x)$: http://mathworld.wolfram.com/ExponentialIntegral.html $$\int \frac{e^x}{x}dx=\text{Ei}(x)+\text{constant}.$$

$$\int \frac{e^x}{x^2}dx=\text{Ei}(x)-\frac{e^x}{x}+\text{constant}.$$ If you don't need a closed form one can express it on the form of infinite series (See the above link).

If you are not familiar with the use of special functions see https://en.wikipedia.org/wiki/Special_functions

About special functions, a paper for general public (pp.18-36 in English) : https://fr.scribd.com/doc/14623310/Safari-on-the-country-of-the-Special-Functions-Safari-au-pays-des-fonctions-speciales