Author Topic: section 4.4  (Read 608 times)

Jiacheng Ge

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section 4.4
« on: November 01, 2018, 11:43:12 PM »
What's the strategy to choose from using the undetermined coefficient method or variation of parameters method?
« Last Edit: November 01, 2018, 11:50:02 PM by Jiacheng Ge »

Monika Dydynski

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Re: section 4.4
« Reply #1 on: November 02, 2018, 08:46:07 AM »
The method of undetermined coefficients will only work for a fairly small class of functions. More specifically, the inhomogeneous term (the right side) must be an exponential, polynomial, sine or cosine, or a combination of these. Also, it is generally only useful for constant coefficient DEs.

The method of variation of parameters is a more general method that can be used for many more cases, although it is a messier process. (I don't want to mislead you by saying it works in all cases, just in case there is some exception outside the scope of this course)


« Last Edit: November 02, 2018, 08:58:14 AM by Monika Dydynski »