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4 votes
0 answers
112 views

Calculate an integral involving polylog functions

Im my recent answer https://math.stackexchange.com/a/4777055/198592 I found numerically that the following integral has a very simple result $$i = \int_0^1 \frac{\text{Li}_2\left(\frac{i\; t}{\sqrt{1-...
Dr. Wolfgang Hintze's user avatar
8 votes
3 answers
1k views

Prove $\int_{0}^{1}\frac1k K(k)\ln\left[\frac{\left(1+k \right)^3}{1-k} \right]\text{d}k=\frac{\pi^3}{4}$

Is it possible to show $$ \int_{0}^{1}\frac{K(k)\ln\left[\tfrac{\left ( 1+k \right)^3}{1-k} \right] }{k} \text{d}k=\frac{\pi^3}{4}\;\;? $$ where $K(k)$ is the complete elliptic integral of the first ...
Setness Ramesory's user avatar
1 vote
0 answers
69 views

Polylogarithm further generalized

Here I proposed a generalized formula for the polylogarithm. However, because of a slight mistake towards the end, visible prior to the edit, I was unaware that it yields just a result of an integral ...
Artur Wiadrowski's user avatar
5 votes
1 answer
193 views

Evaluating $\int_{0}^{1}\mathrm{d}x\,\frac{\operatorname{arsinh}{(ax)}\operatorname{arsinh}{(bx)}}{x}$ in terms of polylogarithms

Define the function $\mathcal{I}:\mathbb{R}^{2}\rightarrow\mathbb{R}$ by the definite integral $$\mathcal{I}{\left(a,b\right)}:=\int_{0}^{1}\mathrm{d}x\,\frac{\operatorname{arsinh}{\left(ax\right)}\...
David H's user avatar
  • 30.7k
2 votes
0 answers
85 views

Complex polylogarithm/Clausen function/Fourier series

Sorry for the confusing title but I'm having a problem and I can phrase the question in multiple different ways. I was calculating with WolframAlpha $$\int \text{atanh}(\cos(x))\mathrm{d}x= i \text{Li}...
Math Attack's user avatar
2 votes
0 answers
68 views

Evaluating $\int\frac{\log(x+a)}{x}\,dx$ in terms of dilogarithms

As per the title, I evaluated $$\int\frac{\log(x+a)}{x}\,dx$$ And wanted to make sure my solution is correct, and if not, where I went wrong in my process. Here is my work. $$\int\frac{\log(x+a)}{x}\,...
Person's user avatar
  • 1,123
6 votes
2 answers
326 views

How to show $\int_0^1\frac{\operatorname{Li}_2\left(\frac{1+x^2}{2}\right)}{1+x^2}dx=\ln(2)G$

I am trying to prove that $$\int_0^1\frac{\operatorname{Li}_2\left(\frac{1+x^2}{2}\right)}{1+x^2}dx=\ln(2)G,$$ where $G$ is the Catalan constant and $\operatorname{Li}_2(x)$ is the dilogarithm ...
Ali Shadhar's user avatar
  • 25.8k
5 votes
1 answer
288 views

Closed forms of the integral $ \int_0^1 \frac{\mathrm{Li}_n(x)}{(1+x)^n} d x $

(This is related to this question). How would one find the closed forms the integral $$ \int_0^1 \frac{\mathrm{Li}_n(x)}{(1+x)^n} d x? $$ I tried using Nielsen Generalized Polylogarithm as mentioned ...
Anomaly's user avatar
  • 107
1 vote
1 answer
122 views

Show that $\int_0^1 \frac{Li_{1 - 2m}(1 - 1/x)}{x} dx = 0$.

I would like to show that,for $m \geq 2$, $$I_m := \int_0^1 \frac{\operatorname{Li}_{1 - 2m}(1 - 1/x)}{x} dx = 0$$ where $\operatorname{Li}_{1 - 2m}$ is the $1-2m$ polylogarithm (https://en.wikipedia....
jvc's user avatar
  • 2,073
2 votes
1 answer
259 views

Generalized formula for the polylogarithm

Some time ago, I discovered the formula for repeated application of $z\frac{d}{dz}$ here. Recently, I thought about taking the function to which this would be applied to be the integral representation ...
Artur Wiadrowski's user avatar
5 votes
3 answers
258 views

How to find the exact value of $\sum_{n=1}^{\infty} \frac{\sin \left(\frac{n \pi}{4}\right)}{n^2 \cdot 2^{\frac{n}{2}}} $?

Once I met the identity $$ \boxed{S_0=\sum_{n=1}^{\infty} \frac{\sin \left(\frac{n \pi}{4}\right)}{2^{\frac{n}{2}}}=1}, $$ I first tried to prove it by $e^{xi}=\cos x+i\sin x$. $$ \begin{aligned} \...
Lai's user avatar
  • 22.3k
2 votes
1 answer
174 views

Calculate the integral of the given polylogarithm function? $\int_0^1\frac{\operatorname{Li}_ 4(x)}{1+x}dx=?$ [closed]

$$\int_0^1 \frac{\operatorname{Li}_2(-x)\operatorname{Li}_2(x)}{x}\,\mathrm dx=?$$ where $$\operatorname{Li}_2(-x)=\sum_{k=1}^{\infty}\frac{(-x)^k}{k^2}$$ for $$|x|>1$$ actually my goal is to edit ...
merve kaya's user avatar
3 votes
1 answer
244 views

How to solve $\int\frac{x\arctan x}{x^4+1}dx$ in a practical way

I need to evaluate the following indefinite integral for some other definite integral $$\int\frac{x\arctan x}{x^4+1}dx$$ I found that $$\int_o^\infty\arctan{(e^{-x})}\arctan{(e^{-2x})}dx=\frac{\pi G}{...
phi-rate's user avatar
  • 2,370
21 votes
3 answers
2k views

Evaluate $\int_0^1\arcsin^2(\frac{\sqrt{-x}}{2}) (\log^3 x) (\frac{8}{1+x}+\frac{1}{x}) \, dx$

Here is an interesting integral, which is equivalent to the title $$\tag{1}\int_0^1 \log ^2\left(\sqrt{\frac{x}{4}+1}-\sqrt{\frac{x}{4}}\right) (\log ^3x) \left(\frac{8}{1+x}+\frac{1}{x}\right) \, dx =...
pisco's user avatar
  • 19.1k
1 vote
0 answers
54 views

Dilogarithm Function on Negative Domain

I'm not that good with math, but somehow ended up solving for $ \int { \ln { (\cosh x) } } \cdot dx $. This has led me to the answer described here. In my case, I need a solution for x > 1, ...
Silver Flash's user avatar

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