7740.10.2
Frobenius method for boundary-value problems

a) Suggested transformation and differential equation in v[x]

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Solve DE using suggested transformation (solution is polynomial) => confluent hypergeometric functions of the first kind

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Limits - boundary behavior

Finite y[0] => C[1]=0

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Limit at origin => regular singular point

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d) Attempt to evaluate limit at infinity (note that [Graphics:Images/7740.10.2.nb_gr_14.gif] decreases faster than any polynomial in x) [note the Bessel case for e = 0 and hypergeometric case for e = 2]

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Empirical search for stable eigensolutions (that approach zero as x approaches infinity)

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Negative e

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Zero e

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Positive e

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Fixed negative C[2]

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Fixed positive C[2]

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Systematic search for eigensolutions

Construct the characteristic equation and solve for eigenvalues

Series[y[x]/.soln/.C[1]->0, {x, 0, 7}]
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Converted by Mathematica      November 21, 2005