1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Exact Differentials

  1. Sep 1, 2010 #1
    I am reading a math review in my thermodynamics text and I a little confused by this. Here is the excerpt:

    Doc-9_1_104_56PM-page-1.jpg

    I am confused by the part where it says
    If they selected x = (y, z) then isn't that saying that x is dependent on y? So how can we just turn around and say y = y(x, z) ? That is, if we selected x as dependent in the first function, why can we turn around and call it independent in the second.

    Sorry, this might be a stupid question. I just don't see why we bother calling variables independent and dependent in a situation like this?
     
  2. jcsd
  3. Sep 1, 2010 #2

    Office_Shredder

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    As a simple example if you had the equation x+y+z=0 you could write any variable as a function of the other two quite simply.

    The dependent/independent lines are obviously blurred here; you just use them for the purposes of being able to describe what counts as a function and what's being considered as a variable when differentiating
     
  4. Sep 1, 2010 #3
    Office Shredder strikes again! Thanks boss. This explanation makes great sense. I figured I was over-analyzing the words here.

    Thanks again!
    ~Casey
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Exact Differentials
  1. Exact differential (Replies: 2)

  2. Exact differentials (Replies: 3)

  3. Exact differentials (Replies: 0)

Loading...