This is coming up a lot in some of my thermo HW, so I'm a little confused about whether or not I'm thinking correctly.(adsbygoogle = window.adsbygoogle || []).push({});

Suppose I have a function [itex]f = f(x,a)[/itex]

where a is some constant. If I take the derivative of f wrt to a, what do I get?

The derivative tells you the change in the function due to some small change in a quantity, so if I want to know how f changes with respect a, how does one interpet this?

a can't change, so it seems that f can't change wrt to a, so [itex] df/da = 0[/itex] seems like the only thing that makes sense, but does it actually?

For example, if [itex]f(x,a) = ax + a[/itex], then should [itex]df/da = 0[/itex] or [itex]df/da = x + 1[/itex] ?

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Derivative wrt a constant?

**Physics Forums | Science Articles, Homework Help, Discussion**