How do you solve a differential equation using undetermined coefficients?

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SUMMARY

The discussion focuses on solving the differential equation y'' - 4y' + 4y = 2e^(2x) using the method of undetermined coefficients. The initial assumption of the particular solution yp as Ae^(2x) was incorrect due to the presence of a double root in the auxiliary equation. The correct form of the particular solution is Ax^2e^(2x), which, when substituted back into the original differential equation, yields the correct results.

PREREQUISITES
  • Understanding of differential equations and their classifications
  • Familiarity with the method of undetermined coefficients
  • Knowledge of auxiliary equations and their roots
  • Basic calculus, particularly differentiation and integration
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  • Practice solving differential equations with double roots
  • Explore variations of particular solutions for different types of non-homogeneous terms
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Students and professionals in mathematics, engineering, and physics who are looking to deepen their understanding of solving differential equations, particularly using the method of undetermined coefficients.

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How do I go about solving a DE using the method of undetermined coeficients in a question like for example;

y''-4y'+4y=2e^2x

I tried assuming the yp to be Ae^2x but when I plugged it into the DE I ended up with 0=2e^2x


??
 
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Since '2' double root of your aux. eq'n.

the yp should be Ax^2e^2x
 
Once you substitute back into the original DE
Do you get:

8Ax^2e^2x + 2Ae^2x = 2e^2x
 

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