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BillhB
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Homework Statement
Find the values of m so that ##y = x^m## is a solution of ##x^2\frac{d^2y}{dx^2} - 3x\frac{dy}{dx} -12y = 0##
Homework Equations
##y = x^m##
##y'=mx^{m-1}##
##y''=(m^2-m)x^{m-2}##
The Attempt at a Solution
So after plugging and chugging we get
$$(m+2)(m-6)x^m = 0 $$
Henceforth m = -2 or m = 6.
All well and good but why don't we look at the case when x = 0. Then the domain of m would be ##(-\infty, 0) \cup (0, \infty)## right?
The question doesn't state we're looking for m's for any possible x, so this seems correct to me. Is it just assumed that is the case? Or am I misunderstanding something?
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