Mathematica 9 is now available
Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2010

[Date Index] [Thread Index] [Author Index]

Search the Archive

repost - expanding inline d[xy]/dx during implicit differentiation

  • To: mathgroup at smc.vnet.net
  • Subject: [mg113146] repost - expanding inline d[xy]/dx during implicit differentiation
  • From: John Accardi <accardi at accardi.com>
  • Date: Fri, 15 Oct 2010 13:51:26 -0400 (EDT)

Thanks in advance for any help .....

Implicit Differentiation

Below, I need to get the inline d[xy]/dx to expand in the Dt output.
Ditto for the output of Solve.  (I have done other implicit differentiation
calculations that have done this correctly.) What is the issue here?

eq5=x^3-3x^2 y+2xy^2==12

x^3-3 x^2 y+2 xy^2\[LongEqual]12


Dt[eq5,x]

-3 x^2 \[DifferentialD]y/\[DifferentialD]x+3 x^2+4 xy 
\[DifferentialD]xy/\[DifferentialD]x-6 x y\[LongEqual]0



Solve[%%,\[DifferentialD]y/\[DifferentialD]x]

{{\[DifferentialD]y/\[DifferentialD]x->(3 x^2+4 xy 
\[DifferentialD]xy/\[DifferentialD]x-6 x y)/(3 x^2)}}



*.nb is located here:

http://www.accardi.com/ImplicitDifferentiationForumQueryTest.nb

Thanks,
Gianni



  • Prev by Date: Re: question for compiling a function
  • Next by Date: Re: A Bug in symbolic summation?
  • Previous by thread: Re: symbolic division of series
  • Next by thread: What generates the In/Out CellLabels and how do I change them?