What Determines Regular and Irregular Singular Points in Differential Equations?

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The discussion focuses on determining and classifying singular points of a given differential equation. It identifies x = 0 as a regular point based on the polynomial in front of y''. The zeros of the polynomial x^2 - 2x + 3 are incorrectly stated, leading to confusion about identifying irregular points. A correction is suggested regarding the factorization of the polynomial, emphasizing the need for accurate root calculations. The conversation highlights the importance of precise mathematical reasoning in classifying singular points in differential equations.
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Homework Statement


Determine singular points of given DE. Classify as regular or irregular

(x^3 -2x^2 + 3x)^2 y'' + x(x-3)^2 y' + (-x-1)y = 0

Homework Equations

The Attempt at a Solution



From the polynomial infront of y'' I get

x^2 (x^2 -2x + 3)^2

right out of the bat I can see that x = 0 is going to be a regular point.

the zeros of x^2 -2x +3 = 1\frac +- \frac {8^{1/2}}{2}

so since the denominator of y' will have x^2 -2x +3 = 1\frac +- \frac {8^{1/2}}{2} to the second power, can I say that x^2 -2x +3 = 1\frac +- \frac {8^{1/2}}{2} are the irregular points then?
 
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Rijad Hadzic said:

Homework Statement


Determine singular points of given DE. Classify as regular or irregular

(x^3 -2x^2 + 3x)^2 y'' + x(x-3)^2 y' + (-x-1)y = 0

Homework Equations

The Attempt at a Solution



From the polynomial infront of y'' I get

x^2 (x^2 -2x + 3)^2

right out of the bat I can see that x = 0 is going to be a regular point.

the zeros of x^2 -2x +3 = 1\frac +- \frac {8^{1/2}}{2}

so since the denominator of y' will have x^2 -2x +3 = 1\frac +- \frac {8^{1/2}}{2} to the second power, can I say that x^2 -2x +3 = 1\frac +- \frac {8^{1/2}}{2} are the irregular points then?
It is not correct to say ##x^2 -2x +3 = 1 \pm\frac {8^{1/2}}{2}##. I think what you mean is ##x^2 -2x +3 = (x-1 + \frac {8^{1/2}}{2})(x-1 - \frac {8^{1/2}}{2})##. That is still not right, though, because you have made a mistake in solving for the roots of ##x^2-2x+3##.
 
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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