Search found 2883 matches
- Thu Oct 29, 2009 5:52 am UTC
- Forum: Mathematics
- Topic: Discontinuous derivative of an explicitly defined function
- Replies: 18
- Views: 4361
I am having trouble thinking of explicitly defined, differentiable functions with discontinuous derivatives in one dimension. This has been a problem that has bothered me since BC Calc, when I was presented an example of an integrable, discontinuous function defined piecemeal by its derivative. This...
My preferred proof for Euler's formula is simply solving a second-order differential equation, although to be rigorous it technically requires proving some differentiation formulae for complex numbers. d^2/dx^2 e^(i x) = d/dx i e^(i x) = i^2 e^(i x) = -e^(i x) So solve the diff eq: d^2y/dx^2 = -y Th...
- Thu Oct 29, 2009 5:23 am UTC
- Forum: The Help Desk
- Topic: Cannot login on Firefox
- Replies: 4
- Views: 575
This problem is odd, but I cannot login to this forum on Firefox, which is by far my prefered browser. After clicking "submit" in the login form, I do go to the page saying I logged in, but when it redirects me to the forum (or anywhere else) it clearly indicates that I am NOT logged in, a...