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Variable transformations
Posted:
Jul 23, 2013 4:43 AM


Say I have some differential equation in terms of the independent variable x and dependent variable f(x). Now say I want to do a coordinate/variable transformation where x=x(u) and I want to write my equation in terms of only u and f(u). By pencil & paper, you can do this by applying the chain rule, but I have a complicated equation and I want to check if I've made an algebra slipup (it involves several dependent and independent variables and up to 4th order derivatives). Is there any way to automate something like this in Mathematica? I've messed around with replacement rules, but I can't get Mathematica to do things quite how I want.
Thanks!



