Solution of Euler Differential Equation Using Ansatz Method

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SUMMARY

The Euler differential equation \(x^{2}y'' + 3xy' - 3y = 0\) can be solved using the Ansatz method by assuming a solution of the form \(y(x) = cx^{m}\), where \(c\) and \(m\) are constants. The derivatives yield \(y'(x) = cmx^{m-1}\) and \(y''(x) = cm(m-1)x^{m-2}\). Substituting these into the equation leads to the characteristic equation \(m^2 + 2m - 3 = 0\), which factors to \((m - 1)(m + 3) = 0\), giving solutions \(m = 1\) and \(m = -3\). The constant \(c\) cannot be determined without initial conditions.

PREREQUISITES
  • Understanding of differential equations, specifically Euler equations.
  • Familiarity with the Ansatz method in solving differential equations.
  • Knowledge of polynomial factorization and solving quadratic equations.
  • Basic proficiency in calculus, including differentiation.
NEXT STEPS
  • Study the general solution of Euler differential equations.
  • Learn about initial value problems and how they affect the determination of constants in solutions.
  • Explore the implications of different values of \(c\) in the context of boundary conditions.
  • Investigate other methods for solving differential equations, such as the method of undetermined coefficients.
USEFUL FOR

Students studying differential equations, mathematicians interested in analytical methods, and educators teaching advanced calculus concepts.

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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?
 
Last edited:
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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