Anti derivative of the function x/lnx

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The discussion centers on finding the antiderivative of the function x/ln(x). It is noted that there is no closed-form solution for this integral using elementary functions. However, a closed expression involving the exponential integral function, denoted as Ei, is provided: the antiderivative can be expressed as -Ei(1, 2ln(x)). The use of the Ei function is highlighted as significant, contributing to deeper insights in mathematical theory, despite the lack of a primitive function for the integral.
Murad A.Omar
hi
how are you all
can you help me in finding the anti derivative of the function
x/lnx
 
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As-salaam alaikum!

There's no closed-form solution for that integral, unfortunately.
 
Although no elementary functions can be found, a closed expression is

[inte]x/Ln(x)dx= -Ei(1,2Ln(x)),

so that you can approximate the values of the function.

P.S: It is not infortunate (for me) that there is no primitive, since the Ei function is an essential ingredient of the theory and has led to marvellous new insights.
 
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