$\displaystyle \int e^{-2x^2-5x-3} \mathrm dx$ with seemingly inescapable trap
4287
Proving $\int_{0}^{\infty} \mathrm{e}^{-x^2} dx = \frac{\sqrt \pi}{2}$
80952
A difficult integral evaluation problem
64896
Dealing with non-integral powers on negative numbers
44737
$ \int_{-\infty}^{\infty} x^4 e^{-ax^2} dx$
65407
Evaluating $\int\limits_0^\infty \frac{\log x} {(1+x^2)^2} dx$ with residue theory
47425
Finding $\int \sec^3x\,dx$
133160
Closed form for $\int_0^\infty\frac{1}{(1+x^2)^s}\,dx$ when $s\in (0.5,\infty)\setminus\mathbb{N}$
110343
Integrating $\rm x^ae^{-bx}$.
68319
How can I evaluate $\int_{-\infty}^{\infty} e^{-x^2} dx$ without using polar coordinates
27347
Verify that $\left|\int_{\gamma} \exp(iz^2)dz\right| \leq \frac{\pi\big(1-\exp(-r^2)\big)}{4r}$ where $\gamma(t)=re^{it}$, for $0\leq t \leq \pi/4$.
126304
Determining bounds for the sum $\sum\limits_{n=1}^\infty \frac{1}{2^n - 3^n }$
146015
Computing $\int \sqrt{x\sqrt[3]{x\sqrt[4]{x\sqrt[5]{x\cdots}}}} \,\mathrm{d}x$
127105
Determining a tricky limit
144039
Computing $ \int_0^{\infty} \frac{ \sqrt [3] {x+1}-\sqrt [3] {x}}{\sqrt{x}} \mathrm dx$
144568
How closely can we estimate $\sum_{i=0}^n \sqrt{i}$
148746
Calculating $\int\frac{e^{iz}}{z}\, dz$ on the semi-circle given by $re^{i\theta}$ where $\theta:\,0\to\pi$
51488
Evaluating $\int^\pi_{-\pi} \cos^3(x) \cos(ax)~dx$