# Search results

1. ### Simple integral, example or general solution correct?

This should be very simple, but I can find a simple example that violates my general conclusion. I clearly must be doing something wrong with my integration by parts. Any suggestions would be great. Define a distribution such that the density; \eta(\vec{x})=\int d\vec{k} f(\vec{x},\vec{k})...
2. ### Potential on a line charge?

I know it seems a bit trivial, but what is the potential right at an infinite uniformly charged line? Irregardless of reference point, the Potential will have a ln|s|, where s is the perpendicular distance to the line. Obviously this would result in infinity. At the same time when I...
3. ### Increasing distance

I'm having trouble getting the answer without doing a guess and check. Q: Find the maximum angle a projectile can be shot so that it's distance from the origin is always increasing. Air resistance negleced. So there is the x and y position based on initial velocity, angle, and time, but I...
4. ### Diffuculty with notation

Difficulty with notation I've always had trouble with notation, since there are so many ways to write the same thing. This one is for Vector Analysis First off, when speaking of unit vectos, such as i, j, k is it ok to use the notation; {\hat i},{\hat j},{\hat k} ? Such as in...
5. ### Your password is 12657 days old, and has therefore expired.

I don't have a Ph.D in Mathematics or anything, but my parents were only 10 years old back then. :rolleyes: Not that I'm worried, just curious if that was a normal message.
6. ### Matrices and Matrix Calculations of Linear Algebra

My intent is to create a thread for people interested in Linear Algebra using Matrices. However, I will explicitly state that I am only a student of this class myself and that many things could end up being wrong or an improper way to teach. I will merely be going along with the class, mostly...
7. ### Intro. to Differential Equations

My intent is to create a thread for people interested in Differential Equations. However, I will explicitly state that I am only a student of this class myself and that many things could end up being incorrect or an improper way to present the material. I will merely be going along with the...