Solve First Order Homogeneous ODE | Constants a and b | Help Needed!

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The discussion centers on solving a first-order homogeneous ordinary differential equation (ODE) given by y'(x) - (a/x)y = b/(x(1+x)^2), where a and b are constants. The initial approach involved using an integrating factor, leading to the integral ∫ x^(-a)/(x(1+x)^2) dx, which complicates the solution with Gauss hypergeometric functions. A suggestion was made to simplify the problem by focusing on the integrating factor x^(-a) and re-evaluating the integral ∫ b/(x^(1+a)(1-x)^2) dx. The participant expresses frustration over making mathematical errors and the time taken to solve the problem, acknowledging its complexity as part of a project. The conversation highlights the challenges of tackling advanced ODEs and the importance of comparing different solution methods.
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Hi, need help solving a first order homogeneous ODE.

y'(x)-(a/x)y = b/(x(1+x)^2) Here a and b are some constants.

Need to solve this for y.

My attempts so far have been to use

img1.gif


But this means solving ∫ x^(-a)/(x(1+x)^2) dx which has solutions in terms of Gauss hyper-geometric functions,

http://en.wikipedia.org/wiki/Hypergeometric_function"

Which lead me to believe I'm going wrong somewhere...

Sorry for the maths format, I'm new to here and don't know how to insert LaTeX.

Thanks
 
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What, he didn't give you an easy one huh? But isn't the integrating factor x^(-a) so that you get:

d(yx^{-a})=\frac{b}{x^{1+a}(1-x)^2}

Now suppose all you had to do was:

\int \frac{b}{x^{1+a}(1-x)^2}dx

Could you use parts say, one, two, three, four times, look at what's happening to the sequence, then come up with a general (infinite-term) expression for the solution that when you checked out the power-series expression for the Hypergeometric series solution reported by Mathematica, the series you get looks like it?
 
thanks for the response Jackmell,

Am currently working on it, though keep making maths errors which are slowing me down.

I agree it would be a good idea to compare, thanks for the tip.

The problem is part of a project, so yea the problems not meant to be easy.
demoralising thing though is that I'm not sure i was supposed to take this long with it!

Konig
 
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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