Solution of Euler Differential Equation Using Ansatz Method

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The discussion focuses on solving the Euler differential equation x²y'' + 3xy' - 3y = 0 using the ansatz y(x) = cx^m. The derivatives y' and y'' are calculated, leading to the characteristic equation m(m-1) + 3m - 3 = 0, which simplifies to m² + 2m - 3 = 0. The roots of this equation are m = 1 and m = -3, indicating the general solution form. The participant concludes that without initial conditions, the constant c cannot be determined. The focus remains on the solution process and the implications of the results.
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Homework Statement


Solve the euler differential equation

\x^{2}y^{''}+3xy'-3y=0
<br /> \int_X f = \lim\int_X f_n &lt; \infty<br />
by making the ansatz y(x)=cx^{m}, where c and m are constants.&lt;br /&gt; &lt;br /&gt; &lt;h2&gt;The Attempt at a Solution&lt;/h2&gt;&lt;br /&gt; &lt;br /&gt; y(x)0=c^{m}&amp;amp;lt;br /&amp;amp;gt; y^{&amp;amp;amp;amp;#039;}(x)=cm^{m-1}&amp;amp;amp;amp;lt;br /&amp;amp;amp;amp;gt; y^{&amp;amp;amp;amp;amp;amp;#039;&amp;amp;amp;amp;amp;amp;#039;}(x)=cm(m-1)^{m-2}&amp;amp;amp;amp;amp;amp;lt;br /&amp;amp;amp;amp;amp;amp;gt; &amp;amp;amp;amp;amp;amp;lt;br /&amp;amp;amp;amp;amp;amp;gt; m(m-1)+3m-3=0&amp;amp;amp;amp;amp;amp;amp;amp;lt;br /&amp;amp;amp;amp;amp;amp;amp;amp;gt; m^2+2m-3=0&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;br /&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; (m-1)(m+3)=0&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;br /&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; m=-3 or m=1&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;br /&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;br /&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; Is this the solution or can c be found?
 
Last edited:
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Latex isn't working on this post so here it is without Latex:

Homework Statement


Solve the euler differential equation

x^{2}y''+3xy'-3y=0

by making the ansatz y(x)=cx^{m}, where c and m are constants.

The Attempt at a Solution



y(x)=cx^{m}
y'(x)=cmx^{m-1}
y''(x)=cm(m-1)x^{m-2}

m(m-1)+3m-3=0
m^2+2m-3=0
(m-1)(m+3)=0
m=3 or m=-1

Is this the solution or can c be found?
 
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Latex maybe out due to technical problems.

Is one sure of the function before the y' term - 3x^{2}?
 
*Correction made* :)
 
Astronuc said:
Latex maybe out due to technical problems.

Is one sure of the function before the y' term - 3x^{2}?

This was merely a typo, the orignal problem still remains...
 
so...er...c?
 
since no innitial conditions were given i shall take irt that c cannot be found.
 

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