Re: Implicit Derivatives

*To*: mathgroup at smc.vnet.net*Subject*: [mg26206] Re: Implicit Derivatives*From*: "Paul Lutus" <nospam at nosite.com>*Date*: Sat, 2 Dec 2000 02:10:35 -0500 (EST)*References*: <9074vq$b19@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

"Tom De Vries" <tdevries at shop.westworld.ca> wrote in message news:9074vq$b19 at smc.vnet.net... > Hello everyone, > > I am teaching a high school calculus class and we are using Mathematica for > part of the course work. In the book CalcLabs with Mathematica they give > a procedure for finding an Implicit Derivative. Here is an example with a > familiar equation.... > > eq = (3 x y == x^3 + y^3) > > eqNew = eq /. y -> y[x] > > deqNew = D[eqNew, x] > > soln = Solve[deqNew, y'[x]] > > > I am wondering if there are other ways to get a similar result to this. > This method makes sense to me but I wondered if there was a more direct > approach? I could not find any information using the Help feature but > perhaps I was just looking in the wrong places? Here is one approach: f = (3 x y[x] == x^3 + y[x]^3) soln = Solve[D[f, x], y'[x]] -- Paul Lutus www.arachnoid.com