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X^2 y''+4xy'+2y=0 cauchy euler equation

User Krsi
by
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1 Answer

4 votes
Let
y=x^r, then


x^2(r(r-1)x^(r-2))+4x(rx^(r-1))+2x^r=0

r(r-1)x^r+4rx^r+2x^r=0

r(r-1)+4r+2=0

r^2+3r+2=0

(r+2)(r+1)=0

r=-1,-2

This admits a general solution of


y=C_1x^(-1)+C_2x^(-2)
User Redct
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