Hmm... I see this: http://latex.codecogs.com/gif.latex?F(x,y)=0%20~~\mbox{and}~~%20\left|%20\begin{array}{ccc}%20F''_{xx}%20&%20F''_{xy}%20&%20F'_x%20\\%20F''_{yx}%20&%20F''_{yy}%20&%20F'_y%20\\%20F'_x%20&%20F'_y%20&%200%20\end{array}\right|%20=%200
Must be a cut and paste kind of thing. On Wed, Aug 31, 2011 at 10:50 PM, Ken Krugler <[email protected]>wrote: > > F(x,y)=0 ~~\mbox{and}~~ > > \left| \begin{array}{ccc} > > F''_{xx} & F''_{xy} & F'_x \\ > > F''_{yx} & F''_{yy} & F'_y \\ > > F'_x & F'_y & 0 > > \end{array}\ > > right| = 0 > > The codecogs.com site says that it's an invalid equation.
