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peterkirby1-Visitor
1-Visitor
October 11, 2010
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Implicit differentiation

  • October 11, 2010
  • 2 replies
  • 10456 views

I'm new to mathcad. Can someone please explain to mein detail the steps needed for mathcad15 to carry out implicit differentiation. The specic example I'm looking at is xy+y^3 = sec(y^2). Thanks in advance. Pete.

Best answer by AlvaroDíaz

Nope. Here is your problem: isn't the same vertical bar which is in the programming toolbar than the used for symbolic combination of more than one symbolic statmen

t. To add more than one symbolic command you mus to type Ctrl + Shift + period. In the image, this was done four times

img.gif

For the Given command I feel that you can learn about it in the quick sheets; they are much better than the usual help. Check the worksheet "

Solving Nonlinear Systems of Equations" under "Solver Equations".

Regards. Alvaro

2 replies

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AlvaroDíaz12-Amethyst
12-Amethyst
October 11, 2010

If you are learn about implicit differentiation, your example isn't the better to an introductory notes. In the attached you can found the explicit derivative of the function implicitly defined by your relationship.

Regards. Alvaro.

    A
    AlvaroDíaz12-Amethyst
    12-Amethyst
    October 12, 2010

    Symbolic solution for the implicit derivative added.

    Regards. Alvaro.

      P
      peterkirby1-VisitorAuthor
      1-Visitor
      October 12, 2010

      Alvaro, many thanks for taking the time to help me. I think I'm able to follow the symbolic solution except for the right hand side of the line starting "eq(x,y,y'):=. It has a symbol I don't recognize, followed by a left-pointing arrow. Can you please tell me the key strokes needed for the right hand side of this expression, then I think I will be ok! Again, many thanks. Peter.

      A
      AlvaroDíaz12-Amethyst
      12-Amethyst
      October 12, 2010

      The left arrow is for symbolic evaluations, inserted with Ctrl+period, can learn about it in quicksheets under "Symbolic Math". This strange symbol in eq(x,y,y') is the ascii Alt+232 and it is only to remember me that the assignation was delayed -can susbtitute it by a letter, like A-, and usually I do this only for break the line. Itis less efficient than the usual way to assign in the same line: so, don't pay attention to it, can do the assignation and the evaluation in the same line, as it is usual.

      Regards. Alvaro.

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