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Solve this differential equation?

GROUPS:

(Edited to add: I may have solved my problem now. See end of post.)

This does not work (edited to fix a mistake of mine):

DSolve[{
  0 == -voltageC0[t] - 2*voltageC0''[t] + 2*voltageC1''[t],
  0 == -voltageC1[t] - 2*voltageC1''[t] + 2*voltageC0''[t]
  }, voltageC0[t], t]

Mathematica replies:

DSolve::overdet: There are fewer dependent variables than equations, so the system is overdetermined.

I cannot make sense of that response from Mathematica. I see two dependent variables, and I see two equations. Two equals two. What is the meaning of Mathematica's response to my query?

Edited to add: This attempt apparently succeeds:

DSolve[{
  0 == -voltageC0[t] - 2*voltageC0''[t] + 2*voltageC1''[t],
  0 == -voltageC1[t] - 2*voltageC1''[t] + 2*voltageC0''[t]
  }, {voltageC0, voltageC1}, t]

The large constant-numerical-values appearing in the solution do surprise me though.

POSTED BY: Joe Donaldson
Answer
8 days ago

From your equation you can deduce that voltageC0 is the same as voltageC1. You only have one differential equation with two unknowns voltage01 and voltage10.

POSTED BY: Gianluca Gorni
Answer
8 days ago

Thanks. I believe adding the two equations shows actually that

0==voltageC0 +voltageC1

However, when I ensure the number of equations matches the number of unkowns (as shown in my now-updated original post), I get a different cryptic error-message from Mathematica. Can anyone make sense of Mathematica's response to my query?

POSTED BY: Joe Donaldson
Answer
8 days ago

Group Abstract Group Abstract