Hats off to Pete! Ampere's Law, differential form <img src="http://www.forkosh.com/mimetex.cgi?\Delta \times \mathbf H = \mathbf J -\frac{\partial }{\partial t} \mathbf D"> <img src="http://www.forkosh.com/mimetex.cgi?\Delta \times \mathbf H = \mathbf J -\frac{\partial }{\partial t} \mathbf D"> Ampere's Law, integral form <img src="http://www.forkosh.com/mimetex.cgi?\oint_C \mathbf H \cdot d \mathbf l = \int_S \mathbf J \cdot d \mathbf A + \frac d{dt} \int_S \mathbf D \cdot d \mathbf A"> <img src="http://www.forkosh.com/mimetex.cgi?\oint_C \mathbf H \cdot d \mathbf l = \int_S \mathbf J \cdot d \mathbf A + \frac d{dt} \int_S \mathbf D \cdot d \mathbf A">
Only problem with this is that if the site www.forkosh.com goes down at any stage, all posts which include LaTeX will "break".
However, pseud0 or zox might want to look at this: http://www.forkosh.com/mimetex.html and think about whether they would like to build this into the sciforums software. (I'm not sure whether it can be done for vbulletin.)
Two of my personal favorites: Leibniz Integral Rule: <img src="http://www.forkosh.com/mimetex.cgi?\frac{\partial}{\partial z} \int_{a(z)}^{b(z)}f(x,z) \, dx = \int_{a(x)}^{b(x)} \frac{\partial f}{\partial z} \, dx + f(b(z),z)\frac{\partial b}{\partial z} - f(a(z),z)\frac{\partial a}{\partial z} "> Holder's Inequality: <img src="http://www.forkosh.com/mimetex.cgi?\mathbb{E} |XY| \leq \left(\mathbb{E} |X|^p \right)^{1/p} \left( \mathbb{E} |Y|^q \right)^{1/q} \, , \, \forall X \in L^p \, , \, Y \in L^q">
latex <img src="../cgi-bin/mimetex.cgi?\large L(x^i,\frac{dx^i}{dt})=\frac{1}{2}\left(\left(\frac{dx}{dt}\right)^2+\left(\frac{dy}{dt}\right)^2+\left(\frac{dz}{dt}\right)^2+\frac{GM}{r}\right)" alt="" border=0 align=middle>
<img src="http://www.forkosh.com/mimetex.cgi?\Gamma^l_{ki} = \frac{1}{2} g^{lj} (\partial_k g_{ij} + \partial_i g_{jk} - \partial_j g_{ki})"> I wanted to try Please Register or Log in to view the hidden image!
