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9 questions with no upvoted or accepted answers
8 votes
0 answers
404 views

Powerful Integral $\int_0^x\frac{t\ln(1-t)}{1+t^2}\ dt$

This integral can be found in Cornel's book, (Almost) Impossible Integral, Sums and Series page $97$ where he showed that $$\int_0^x\frac{t\ln(1-t)}{1+t^2}\ dt=\frac14\left(\frac12\ln^2(1+x^2)-2\...
Ali Shadhar's user avatar
  • 25.8k
6 votes
1 answer
285 views

Calculate $\int _0^1\frac{\arcsin ^2\left(x\right)\ln \left(x\right)\ln \left(1-x\right)}{x}\:\mathrm{d}x$

this integral got posted on a mathematics group by a friend $$I=\int _0^1\frac{\arcsin ^2\left(x\right)\ln \left(x\right)\ln \left(1-x\right)}{x}\:\mathrm{d}x$$ I tried seeing what I'd get from ...
logandetner's user avatar
3 votes
0 answers
316 views

Two tough integrals with logarithms and polylogarithms

The following two integrals are given in (Almost) Impossible Integrals, Sums, and Series (see Sect. $\textbf{1.55}$, page $35$), $$i) \int_0^{\pi/2} \cot (x) \log (\cos (x)) \log ^2(\sin (x)) \...
user97357329's user avatar
  • 5,495
3 votes
0 answers
106 views

Proving that swapping the order of this summation is justified

I'm unsure if this has been discovered already, but it's heavily related to my current research, particularly to this question of mine (this conjecture was also originally posted at the beginning of ...
teadawg1337's user avatar
2 votes
1 answer
86 views

Is there a nice way to represent $\sum_{n=1}^\infty \frac{(-1)^{n+1}H_n}{n+m+1}$?

Here, $H_n$ denotes the harmonic number. More colloquially, is there any way to represent $$\int_0^1 x^{n-1}\log^2\left(1+x\right)\ \mathrm{d}x$$ in a nice way? The latter is corollary to the original ...
zalm's user avatar
  • 125
2 votes
0 answers
368 views

Upper bound the Polylogarithm $\sum_{n=1}^\infty \frac{x^n}{n^2}$

Let $x \in (0,1)$ be some real number, we can then consider the Polylogarithm: $$\operatorname{L}_2(x)=\sum_{n=1}^\infty \frac{x^n}{n^2}$$ It is not hard to see that the following upper bound holds: $$...
HolyMonk's user avatar
  • 1,135
1 vote
0 answers
119 views

Generalized form of this Harmonic Number series $\sum_{n=1}^{\infty} \frac{{H_n}x^{n+1}}{(n+1)^3}$

i've tried to Evaluate $$\int_{0}^{\frac{\pi}{6}}x\ln^2(2\sin(x))dx$$ without using Contour integral first i changed $2\sin(x)$ into polar form ,and i got $$\int_{0}^{\frac{\pi}{6}}x\ln^2(2\sin(x))dx ...
Unik Sillavich's user avatar
0 votes
1 answer
148 views

Evaluate: ${{\int_{0}^{1}\frac{\ln(1+x)^5}{x+2}dx-\int_{0}^{1}\frac{\ln(1+x)^5}{x+3}dx+5\ln2\int_{0}^{1}\frac{\ln(1+x)^4}{x+3}dx}}$

Evaluate: $${{I=\int_{0}^{1}\frac{\ln(1+x)^5}{x+2}dx-\int_{0}^{1}\frac{\ln(1+x)^5}{x+3}dx+5\ln2\int_{0}^{1}\frac{\ln(1+x)^4}{x+3}dx.}}$$ The answer is given below: $$ I=-\frac{7}{12}\pi^4\ln^2(2)-\...
Setness Ramesory's user avatar
0 votes
0 answers
42 views

Upper-bounding $\exp \log^{d} \frac{\log n}{n}$

How would you upper-bound this expression? $$f(n, d) = \exp \log^{d} \frac{\log n}{n}$$ If $d = 1 $ this woulld simplify to $\frac{\log n}{n}$. Any suggestions on how to upperbound it? Notation ...
Daniel's user avatar
  • 2,670