Integrating a Bessel Function with a Constant: Is This the Correct Approach?

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The discussion centers on the integration of the Bessel function J3/2(x) divided by x², specifically evaluating the integral from 0 to infinity. The user attempts to apply a substitution method involving a constant 'a' and questions whether their approach is correct. After some back-and-forth, it is clarified that one 'a' cancels out during the substitution process, leading to the correct form of the integral. The final resolution indicates that the substitution y = ax simplifies the problem effectively. This approach confirms the integration technique for Bessel functions in the context of the given problem.
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Homework Statement



I've been given that the Bessel function

∫(J3/2(x)/x2)dx=1/2π (the integral goes from 0 to infinity).

Homework Equations



∫(J3/2(ax)/x2)dx,

where a is a constant.

The Attempt at a Solution



Is the following correct?

a2∫(J3/2(ax)/(ax)2)dx=a2/2π

(This is just a part of a triple integral. We are not asked nor expected to bother too much with the Bessel function, since it is not the focus of the problem).
 
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No, I think one of the 'a's goes away. Do the substitution again: y = ax. With a>0.
 
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dextercioby said:
No, I think one of the 'a's goes away. Do the substitution again: y = ax. With a>0.

Oh, of course. I then get dx=dy/a, which solves the problem for me. Thanks!
 
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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