Skip to main content
projectilemotion's user avatar
projectilemotion's user avatar
projectilemotion's user avatar
projectilemotion
  • Member for 8 years, 3 months
  • Last seen this week
59 votes
Accepted

Mathematical joke regarding three people leaving a house

55 votes
Accepted

Weird large K symbol

27 votes

Did Pólya say, "can" or "cannot"?

19 votes

What is the general solution to $2 \cos^2 x-\cos x=0$?

19 votes
Accepted

Evaluating $\int_{0}^{\frac{\pi}{2}} x^n \csc(x) dx$

18 votes

Integration of secant

14 votes
Accepted

How do I evaluate $\int_{1/3}^3 \frac{\arctan x}{x^2 - x + 1} \; dx$?

14 votes
Accepted

How do I apply the product (capital pi) symbol here?

12 votes
Accepted

Terrible equation $(x+x^{\ln x})^{10}=2^{10}$

12 votes

Value of $I=\inf_{f\in S} \int_0^1 f(x)^2 \, \text{d}x$

12 votes

Evaluating the following integral: $\int_{0}^{\infty }\frac{x\cos(ax)}{e^{bx}-1}\ dx$

12 votes
Accepted

Intuitively understanding why $\pi_1(S^2) = 0$

10 votes
Accepted

Solving the ODE $(x^2 y-1)y'-(xy^2-1)=0$

8 votes

Proof for integral representation of Lambert W function

8 votes
Accepted

Finding $\int_0^7 g(r)~dr$ from $ g(r)=\begin{cases} \sqrt{9-(r-3)^2}, & 0\le r<3 \\ r+2, & 3\le r<5 \\ \sqrt{4-(r-5)^2}, & 5 \le r \le 7\end{cases} $

8 votes
Accepted

Finding the next term in the sequence: $2028, 4624, 6498, 11638$

7 votes
Accepted

Evaluating the indefinite integral $\int \frac {x^7-1}{\log x}dx$

7 votes

hint on solving $1+y'^2-y\cdot y''=0$?

7 votes
Accepted

How to get the interval after change of variables?

7 votes
Accepted

The integral $\int_{-\infty}^{\infty}\frac{1}{R^2+z^2}e^{-\alpha \sqrt{R^2+z^2}}\mathrm{d}z$

7 votes

Solution of the differential equation $y=x \cdot \frac{dy}{dx}+\frac{b}{\frac{dy}{dx}}$

7 votes
Accepted

Solving a second-order linear ODE: $\frac{d^2 y}{dx^2}+(x+1)\cdot \frac{dy}{dx}+5x^2\cdot y=0$

7 votes

Integrating $e^x / (e^x - 2)$

6 votes

Bob took a quiz

6 votes

A simple proof by induction $P(n) = \frac{6^{2n} - 3^n}{11} \in \mathbb{N}$

6 votes
Accepted

How to transform a PDE into canonical form

6 votes
Accepted

Finding $\int \frac{\sqrt{\cot(x)} - \sqrt{\tan(x)}}{4+3 \sin^2 (x)} \ \mathrm d x$

6 votes

Argument Principle - from J.Bak and D.Newman textbook

6 votes
Accepted

Prove that $ \int_0^1\frac{x\ln(x)}{1+x^2+x^4}dx=\frac{1}{36}\Big(\psi^{(1)}(2/3)-\psi^{(1)}(1/3)\Big) $

5 votes
Accepted

Evaluating the integral $\int_{0}^{\infty}\frac{\sin(xy)}{1+x^2+y^2}dx$ for all $y$.

1
2 3 4 5
16