## #math - Thu 26 Apr 2007 between 02:08 and 02:19

### NY Lost Funds

 gtp if dg/dt = 0 then df/dg DNE that's allI acn prove to you that f is a differentiable function of f from the equation he gave mef is a differentiable function of g*f=0 g=0sorrydf/dt=0 dg/dt=0so that takes care of the "exception" Kiryn hey whats a vertex perpendicular TRWBW Kiryn: is that the start of a joke? i don't know, what's a vertex perpendicular... Kiryn err i meant perpendicular gtp @jinc there's an infinite set of solutions mbot Maybe you meant: join kind Kiryn sorry i copied and pasted it from a tutorial TRWBW Kiryn: there is a vertex bisector, a line that bisects the angle at a vertex of a polygon Kiryn TRWBW, I just meant perpendicular. not vertex perpendicular gtp df/dg = (cos t + b)/ (a - sin t), that's all you can get, there's an infinite set of functions of f and g various forms TRWBW Kiryn: perpendicular to a line is another line that meets it at right angles.Kiryn: a more precise definition depends on the type of geometry you are doing demio % D [Arctan[x/y], x] mbot demio: Derivative[1][Arctan][x/y]/y Kiryn TRWBW, http://www.riemers.net/eng/Tutorials/XNA/Csharp/Series1/Lighting_basics.php demio wtf Kiryn thats where im reading about it demio % D [Atan[x/y], x] mbot demio: Derivative[1][Atan][x/y]/y demio >_>% D [Arctan[x/y], x] mbot demio: Derivative[1][Arctan][x/y]/y gtp demio derivative of arctan(x) is 1/(1+x^2) TRWBW Kiryn: do you know differential geometry? Steve|Office demio: http://www.brainyquote.com/quotes/quotes/a/alberteins133991.html demio what about arctan(x/y) Kiryn i have no idea what that means demio dx gtp so derivative of artan(x/y) is (1/(1+x^2))*(1/y) TRWBW Kiryn: how about vector calculus? gtp chain ruleopps Kiryn never did calculus TRWBW Kiryn: linear algebra?