Partial derivative question

  1. tony873004

    tony873004 1,585
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    Gold Member

    What's the difference between [tex]\partial ^2 x[/tex] and [tex]\partial x^2 [/tex]?

    Is [tex]\partial ^2 x[/tex] the same as [tex]\left( {\partial x} \right)^2 [/tex] like [tex]\sin ^2 x$[/tex] is the same as [tex]\left( {\sin x} \right)^2 [/tex]?

    Thanks!
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. If you have [tex] \frac{\partial^2 x}{\partial t^2} [/tex], this translates to [tex] \frac{\partial}{\partial t} \frac{\partial x}{\partial t} [/tex]. In other words, in derivative notation, it's common to write [tex] \partial t * \partial t [/tex] as [tex] \partial t^2 [/tex]. Does that help?
     
  4. tony873004

    tony873004 1,585
    Science Advisor
    Gold Member

    so does it mean the second partial derivative, rather than squaring something?
     
  5. In the case of [tex] \frac{\partial^2 x}{\partial t^2} [/tex], it means the second partial derivative of a function x with respect to t. You can think of the "partial" terms as being squared, but I'm not sure how that would be of any help unless you're having to separate something like [tex] \frac{\partial^2 x}{\partial t^2} [/tex], as was done above. Is there a particular problem that's troubling you?
     
  6. tony873004

    tony873004 1,585
    Science Advisor
    Gold Member

    Yes, this is a small part of a larger problem. But I think I can get it now that I understand the notation. If I get stuck, I'll post the entire problem. Thanks!
     
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