Undetermined Coefficients
We'll solve some second order equations using the method of undetermined coefficients. We'll use the computer to do the algebra.
First Equation:
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print(); # input placeholder
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The characteristic equation is:
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print(); # input placeholder
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print(); # input placeholder
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The general solution to the homogeneous equation is
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print(); # input placeholder
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The trial solution for the particular solution is:
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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We collect all the coefficients and then solve the linear system.
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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Second Equation
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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We write down our trial solution.
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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Third Equation
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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We write down our trial particular solution.
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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print(); # input placeholder
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