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Past Problems List (Integration Contest)

Season 1:

\(\displaystyle 1:\int_0^a \frac{\ln x}{\sqrt{ax-x^2}}dx\quad\int\sin(2015 x)\sin^{2013}xdx\quad\int _0^\infty{(\frac { sin(x) }{ x } })^2dx\quad\int_0^{\pi/2}\frac{\ln(\cos x)}{\sin{x}}dx\quad\int_0^ \infty\frac{dx}{1+x^n}\)

\(\displaystyle 6:\int_0^{\pi/2}\frac{\sin^2x}{\sin x+\cos x}dx\quad\int_0^\pi\dfrac{1}{(\sqrt{10}+ \cos x)^3}\quad\int_0^{\frac{\pi}{2}}\frac{dx}{1+8\sin^2(\tan x)}\quad\int_0^1\ln\left(\frac{1+x}{1-x}\right)\frac{dx}{x\sqrt{1-x^2}}\int_0^\infty\frac{\sin^3x}{x^2}dx\)

\(\displaystyle 11:\int_{0}^{\infty}\dfrac{\log{x}}{x^2+a^2}dx\,a>0\quad\int_{-\infty}^\infty\frac{\cos (\arctan 2x)}{(1+x^2)\sqrt{1+4x^2}}dx\quad\int_0^\infty\frac{x^n}{e^x-1}dx\quad\int_0^1 \ln(\frac{3+x}{3-x})\frac{dx}{\sqrt{x(1-x)}}\quad\int_0^1\frac{1}{\ln{x}}+\frac{1}{1-x}dx\)

\(\displaystyle 16:\int_0^{\frac\pi2}\cos^{n-1}x\cos{ax}dx\quad\int_{-1}^1\frac{dx}{\sqrt{(1-x)(1+x)^2}}\quad\int_0^{\pi/4}\tan^{1/3}xdx\quad\int_{\frac{-1}{\sqrt{3}}}^{\frac{1}{\sqrt{3}}}\frac{x^4}{1-x^4}\cos^{-1}{(\frac{-2x}{1+x^2})}dx\)

\(\displaystyle 20:\int_0^1\frac{\sinh^{-1}(x)-\log((\sqrt{2}-1)\sqrt{x}+1)}{x}dx\quad\int_0^\infty\frac{dx}{x^4+2\cos(2\theta)x^2+1}\quad\int_0^a \frac{xdx}{\cos(x)\cos(a-x)}\quad\int_0^{\frac{\pi}{4}}\ln{\tan(x)}dx\)

\(\displaystyle 24:\int_0^1\operatorname{arcsech}x\arcsin{x}dx\quad\int_0^1ln(ln(\frac{1}{x}))dx\quad\int_0^\infty\frac{\ln{x}}{\cosh{x}}dx\quad\int_0^\infty\ln^2{\tanh{x}}dx\quad\int_{-\infty}^\infty\frac{\sinh{2x}\cos{2x}}{\sinh{\pi x}}dx\)

\(\displaystyle 29:\int_0^1x^2\arctan{x^2}dx\quad\int_1^\infty\frac{x-\left\lfloor x\right\rfloor-0.5}{x}dx\quad\int_0^\pi\ln{(1-2a\cos{x}+a^2)}dx\quad\int_{-\infty}^\infty\frac{x\sin(x+\sin x)e^{\cos x}}{1+x^2}dx\)

\(\displaystyle 33:\int_0^\infty\frac{\sqrt{t}\log(2t+1)}{(t+1)(2t+1)}dt\quad\int_{-\infty}^\infty\frac{\cos(s\arctan(ax))}{(1+x^2)(1+a^2x^2)^{s/2}}dx\quad\int_0^\infty\frac{\arctan(\frac{x^2}{x^2+1})}{x^4+1}dx\quad 36A:\int_{-1}^1\frac{x^a}{1+e^{bx}}dx\)

\(\displaystyle 36B:\int_0^\frac{\pi}{2}\frac{\tan{x}\sec{x}}{(\tan x+\sec x)^n}dx\quad\int_0^1\ln{x}ln(1-x)dx\quad\int_0^\pi\frac{2+2\cos(x)-\cos((2^{8}-1)x)-2\cos(2^{8}x)-\cos((2^8+1)x)}{1-\cos(2x)}\)

\(\displaystyle 39:\int_0^\infty\frac{\arctan(x)\arctan(2x)}{x^2}dx\quad\int_{-\infty}^\infty\frac{\cos(ax^2)-\sin(ax^2)}{1+x^4}dx\quad\int_{0}^{\pi/12} \ln(\tan(x)) dx\quad\int_0^1\frac{1}{x}\frac{\ln{x}}{\sqrt{x}}dx\)

\(\displaystyle 43:\int_0^\frac{\pi}{2}\sqrt{1+\sin^2{x}}dx\quad\int_0^\infty\frac{\sinh(ax)\sin(bx)}{(\cosh(ax)+\cos(bx))^2}dx\)

Season 2:

\(\displaystyle 1:\int_0^1\frac{x\ln{x}}{\sqrt{1-x^2}}dx \quad\int_0^\infty\frac{x\cos(x^3)}{e^{x^3}}dx\quad\int_0^\frac{\pi}{2}\tan^\frac{3}{5} {x}dx\quad\int_0^1\arctan(P(x))\arctan{\sqrt{\frac{x}{1-x}}}dx\quad\int_0^{\pi /2}\arctan{\frac{1729}{cos^2{x}}}dx\)

\(\displaystyle 6:\int_a^b\arccos(\frac{x}{\sqrt{(a+b)x - ab}})dx\quad\int_0^\infty [x^{v-3}(\gamma x+\log\Gamma (1+x))]dx\quad\frac{1}{\sqrt{2\pi}}\int_{-\infty}^\infty e^{-a^2t^2}e^{i\omega t}dt\int\frac{x^2+20}{(x\sin{x}+5\cos{x})^2}dx\)

\(\displaystyle 10:\int_0^\frac{\pi}{2}\frac{1}{(9\tan^2{x}+16)^3}dx\quad\int_0^1\frac{\ln{(x+1)}}{(x+1)(x^2+1)}dx\int_0^\frac{\pi}{2}\sin^{a-1}{(\theta)}\cos^{2t-a}{(\theta)}\sin{(2t\theta)}d\theta\quad\int_0^1\ln(\frac{1+x}{1-x})dx\)

\(\displaystyle 14:\int^1_0\frac{1-x}{\ln{x}}(x+x^2+x^{4}+x^{8}+\cdots )dx\quad\int_\frac{-\pi}{2}^\frac{\pi}{2}\cos(x\tan(\theta))d\theta\quad\int^1_0\frac{t\arccos{t}}{1+t^4}dt\quad\int_{-\infty}^\infty\frac{x^2}{x^4-x^3+x^2-x+1}dx\)

\(\displaystyle 18:\int_0^\infty\frac{\log^2{t}}{1+t^2}dt\quad\int^\frac{\pi}{3}_0\ln^{2}(\frac{\sin{x}}{\sin(\frac{\pi}{3}+x)})dx\quad\int_0^\infty \frac{dx}{(1+x)^3 +1}\quad\int_\frac{-\pi}{2}^\frac{\pi}{2}\frac{\ln(1+ b\sin{x})}{\sin{x}}dx\quad\int_0^\pi\frac{x\sin{x}}{(\cos^2{x}+3)^2}dx\)

\(\displaystyle 23:\int_0^1\log(1+x)\log(1-x^3)dx\quad\int_0^\frac{\pi}{2}\frac1{\sin^8{x}+\cos^8{x}}dx\quad\int^\frac{\pi}{2}_0\frac{\ln(\sin{x}) \ln(\cos{x})}{\tan{x}}dx\quad\int_0^\pi e^{2\cos{x}}\sin^2{(\sin{x})}dx\)

\(\displaystyle 27:\int^2_0\frac{dx}{(2x^2-x^3)^{1/3}}\quad\int_0^\infty\frac{x^5\sin{x}}{(1+x^2)^3}dx\int_0^1\frac{\ln(\cos(\frac{\pi x}{2}))}{x(x+1)}dx\quad\int^\frac{\pi}{8}_0\ln{\tan{2x}}dx\quad\lim_{n\to\infty}\int_0^1\frac{x^n-x^{2n}}{1-x}dx\)

\(\displaystyle 32:\int_0^\pi t^2\ln^2{(2\cos(\frac{t}{2}))}dt\quad\int_0^\infty\arcsin{e^{-x}}dx\quad\int_0^\infty(\frac{\sin{x^2}}{x^2})\cdot (x^2+x-1)dx\quad\int_0^\infty\frac{\ln(\frac{1+x^a}{1+x^b})}{(1+x^2)\ln{x}}dx\)

\(\displaystyle 36:\int_0^\infty\frac{\sin{x}}{e^x-1}dx\quad\int^\frac{\pi}{2}_0\cot(\frac{\theta}{2})\sqrt{\cos{\theta}}\ln{\cos{\theta}}d\theta\quad\int_0^2\frac{\ln((1-0.25x^2)^3+x^3)-3\ln{x}}{(1+0.25x^2)\ln(1-0.25x^2)-(1+0.25x^2)\ln{x}}dx\)

\(\displaystyle 39:\int_0^\infty(\frac{\sin{x}}{x}-\frac1{1+x})\frac{dx}{x}\quad\int_0^\frac{\pi}{2}x(\frac{\ln(\sin{x})-2}{\sqrt{\sin{x}}})\cot{x}dx\quad\int\sqrt{x+\sqrt{x^2+2}}dx\quad\int_0^\frac{\pi}{2}\ln{(2\cos(\frac{x}{2}))}dx\)

\(\displaystyle 43:\int\frac{x^3e^{x^2}}{(x^2+1)^2}dx\quad\int_0^\infty\frac{\ln{(1+x)}}{\ln^2{x}+\pi^2}\frac{dx}{x^2}\quad\int_0^\frac{\pi}{2}\sin^6{x}\tan{x}\sin{\tan{x}}dx\quad\lim_{n\to\infty}\int_0^\frac{\pi}{4}n(\cos^{2n}x-\sin^{2n}x)\tan{2x}dx\)

\(\displaystyle 47:\int_0^\infty e^{-x^2}\ln{x}dx\quad\int_0^\frac{\pi}{2}\frac{\csc{x}\sqrt{\tan{x}}}{\sin{x}+\cos{x}}dx\quad\int_0^1\ln{(\Gamma(x))}dx\quad\int_0^\infty\frac{\ln(1+x)}{\sqrt[4]{x^3}(1+x)}dx\)

Season 3:

\(\displaystyle 1:\int_0^1\frac{\cosh(a\log(x))\log(1+x)}{x}dx\quad\int_0^1\frac{(x^{2}+1)\arctan{3x}}{x}dx\quad\int_0^1\frac{\ln{x}\ln^2(1+x)}{x}dx\quad\int_0^1\frac{{\rm Li}_3^2(-x)}{x^2}dx\)

\(\displaystyle 5:\int_0^\infty\frac{\ln(x^2+1)\arctan{x}}{e^{\pi x}-1}dx\quad\int_0^\infty\frac{\ln{x}}{(x+a)^2+b^2}dx\quad\int_0^\infty\frac{\ln x}{x^n+1}dx\quad\int_0^\frac{\pi}{2}\ln^2\big(a\sin\theta\big)d\theta\)

\(\displaystyle 9:\int_0^1Li_2^2(x)dx\quad\int_0^1(x-1)e^{-x}\ln{x}dx\quad\int_0^1\frac{t^{\alpha-1}-t^{\beta-1}}{(1+t)\ln{t}}dt\quad \int_0^\infty(\frac{\ln{x}\arctan{x}}{x})^2dx\quad\int_0^{2\pi}e^{\cos\theta}\cos\big(n\theta-\sin\theta\big)d\theta\)

\(\displaystyle 14:\int_0^\infty\ln{x}[\ln(\frac{x+1}{2})-\frac{1}{x+1}-\psi(\frac{x+1}{2})]dx\)

These are copy-pasted problems from past contests in chronological order. I will continually update with the new contests.

Note by Jasper Braun
7 months, 1 week ago

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Season 1 also has \(4\) more problems, \(41\) to \(44\). Ishan Singh · 7 months, 1 week ago

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@Ishan Singh Thanks I've added and completed. Jasper Braun · 7 months, 1 week ago

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