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

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  • Subject: [mg113179] Re: repost - expanding inline d[xy]/dx during implicit
  • From: Bob Hanlon <hanlonr at>
  • Date: Sat, 16 Oct 2010 13:13:47 -0400 (EDT)
  • Reply-to: hanlonr at

xy is a separate symbol not the product of x and y.  Add a space or an explicit times, i.e., x*y

Bob Hanlon

---- John Accardi <accardi at> wrote: 

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


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


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

*.nb is located here:


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