Solving the Euler Cauchy Equation: Finding the General Solution

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To solve the Euler-Cauchy equation x^2y" - 2y = 0, a trial solution of the form y = xr is suggested, where r is an unknown constant. The characteristic equation derived from this approach is k(k-1) - 2 = 0. The general solution can be expressed as y = c1|x|^k1 + c2|x|^k2 for x in the intervals (-∞, 0) and (0, ∞). This method is standard for second-order ordinary differential equations of this type. Understanding these steps is crucial for finding the general solution effectively.
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Homework Statement



Find the general solution of x^2y" - 2y = 0


Homework Equations





The Attempt at a Solution



Can anyone tell me how to find the general solution of the Euler Cauchy equation. How do we make it into one?? Thanks.
 
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there is a general method for solving 2nd order ODE of the form y''+f(x)y+g(x)=0 that you can look up in any self respecting book on differential equations. for instance boyce & diprima
 
engineer_dave said:

Homework Statement



Find the general solution of x^2y" - 2y = 0


Homework Equations





The Attempt at a Solution



Can anyone tell me how to find the general solution of the Euler Cauchy equation. How do we make it into one?? Thanks.
Why would you be given the problem of solving an Euler-Cauchy equation if you were told nothing beforehand about solving such a thing?

Try a "trial solution" of the form y= xr where r is an unknown number.
 
The characheristic equation here is k(k-1)-2=0. The solution would then be y=c_1|x|^{k_1}+c_2|x|^{k_2} on (-\infty,0)\cup (0,\infty).
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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