Re: Implicit Derivatives

• To: mathgroup at smc.vnet.net
• Subject: [mg26214] Re: [mg26193] Implicit Derivatives
• From: "Matt Herman" <Henayni at hotmail.com>
• Date: Sat, 2 Dec 2000 02:10:41 -0500 (EST)
• References: <200012010302.WAA11206@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

```Yes,

Here is the procedure for dy/dx, t can be adapted for other variables.

f[eq_] := Module[{j = Dt[eq]}, j = j /. Dt[x] -> 1; Solve[j, Dt[y]]]

Matt Herman
----- Original Message -----
From: "Tom De Vries" <tdevries at shop.westworld.ca>
To: mathgroup at smc.vnet.net
Subject: [mg26214] [mg26193] Implicit Derivatives

> 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?
>
> Thanks,
>
> Tom De Vries