"Textbook" Solutions to Second-Order Homogenous ODEs with Constant Coefficients

We write a general form for the left-hand-side of the homogeneous ODE with constant coefficients β and γ.

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Guess a solution and substitute it into the left-hand side of the ODE:

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This will be a solution when the resulting quadratic expression in λ is equal to 0:

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Set the two solutions to λMinus and λPlus

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The linear combination of the two solutiions is the general solution, here we set the two arbitrary constants.

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This will demonstate that our general solution is, in fact, a solution.

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