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A comment on Ten Lessons I Wish I Had Learned Before Teaching Differential Equations [pdf]. Parent comment

Re:Ten Lessons I Wish I Had Learned Before Teaching Differen... by wiredfool on Monday November 13, 2023 @08:26AM (#38249857)
My grad school was basically working through F=Ma-Cv-Kx in all it's expanding varied glory, working up to full blown finite element analysis.

Ultimately it all comes down to choosing the most convenient basis functions for the questions you're answering.

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Re:Ten Lessons I Wish I Had Learned Before Teaching Differen... by JadeNB on Monday November 13, 2023 @05:24PM (#38256208)
> My grad school was basically working through F=Ma-Cv-Kx in all it's expanding varied glory, working up to full blown finite element analysis.

If I'm understanding correctly, you want another = there for a standard damped spring: F = ma = -Cv - Kx.

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Re:Ten Lessons I Wish I Had Learned Before Teaching Differen... by denotational on Monday November 13, 2023 @05:42PM (#38256387)
F is a forcing function, not the resultant force. It’s often arranged this way with all the derivatives on one side (as opposed to having the resultant force, ma, on one side of the equality by itself) so that it matches the general form of a non-homogeneous second-order linear differential equation.

(At least I assume this is what the original commenter meant!).

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Re:Ten Lessons I Wish I Had Learned Before Teaching Differen... by JadeNB on Monday November 13, 2023 @09:05PM (#38258039)
Ah, that makes more sense. Thanks!
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