Can Anyone Solve the Integral of 1/ln(x)?

  • Thread starter Thread starter Dell
  • Start date Start date
  • Tags Tags
    Integral
Click For Summary
SUMMARY

The integral of the function f(x) = 1/ln(x) does not have a closed form solution. Users in the discussion attempted substitution with t = ln(x), leading to the integral ∫(e^t/t) dt, which remains unresolved. Mathematica confirms that the result is LogIntegral[x], indicating that the integral is best expressed in terms of special functions rather than elementary functions. The discussion also references a series solution found in an integral table.

PREREQUISITES
  • Understanding of integral calculus and substitution methods
  • Familiarity with special functions, specifically LogIntegral
  • Basic knowledge of series expansions in calculus
  • Experience with computational tools like Mathematica
NEXT STEPS
  • Research the properties and applications of the LogIntegral function
  • Explore advanced techniques in integration, such as integration by parts
  • Study series solutions for integrals and their convergence
  • Learn how to use Mathematica for symbolic integration tasks
USEFUL FOR

Mathematicians, calculus students, and anyone interested in advanced integration techniques and special functions.

Dell
Messages
555
Reaction score
0
how would you integrate the following, seemingly simple, function.

f(x)=1/ln(x)

what i tried to do was substitution
t=ln(x)
x=et
dt=dx/x

but from here i get to an integral of \int((et)/(t))dt, no idea how to continue, tried integration in prts but keep going in cirlces, can anyone see how to do this?
 
Physics news on Phys.org
When I plug it into Mathematica, I get
LogIntegral[x]
as the answer.

So I think there is no closed form.
 
Dell said:
\int((et)/(t))dt, no idea how to continue, tried integration in prts but keep going in cirlces, can anyone see how to do this?

My integral table has this, but it is a series solution.

=ln(t)+t+{{t^2}\over{(2)\;2!}}+{{t^3}\over{(3)\;3!}} + ...
 

Similar threads

  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 26 ·
Replies
26
Views
1K
  • · Replies 105 ·
4
Replies
105
Views
7K
  • · Replies 54 ·
2
Replies
54
Views
15K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 3 ·
Replies
3
Views
7K
Replies
2
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 23 ·
Replies
23
Views
2K