What is the General Solution for a Differential Equation with Complex Roots?

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SUMMARY

The general solution for the differential equation \((D^2 + 2D + 10)^2 * (D^2 - 2D - 3)y = 0\) is derived from the roots \(-1 + 3i\) and \(-1 - 3i\) with multiplicity 2, along with the real root \(3\). The complete solution is expressed as \(y = Ae^{3x} + Be^{-x} + Ce^{-x}\cos(3x) + Dxe^{-x}\cos(3x) + Ee^{-x}\sin(3x) + Fxe^{-x}\sin(3x)\). This formulation confirms the correct handling of complex roots and their contributions to the general solution.

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  • Understanding of differential equations and their solutions
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  • Knowledge of the method of undetermined coefficients
  • Proficiency in using the operator \(D = d/dx\)
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  • Study the method of solving higher-order differential equations
  • Learn about the application of complex roots in differential equations
  • Explore the use of the operator method in differential equations
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Students and educators in mathematics, particularly those focusing on differential equations, as well as anyone seeking to deepen their understanding of complex roots in mathematical solutions.

jbord39
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Homework Statement



(D^2 + 2D + 10)^2 * (D^2 - 2D -3)y = 0.

Homework Equations



D = d/dx

The Attempt at a Solution



Solving for the roots gives:

-1 + 3i, -1 - 3i <== both of multiplicity 2
and 3, -1.

So the general solution should be:

y = Ae^(3x) + Be^(-x) + Ce^(-x)cos(3x) + Dxe^(-x)cos(3x) + Ee^(-x)sin(3x) + Fxe^(-x)sin(3x)

Am I handling this correctly?

Thanks
 
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Looks ok to me.
 
Thanks for looking at it.
 

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