Determining Cauchy principal value of divergent integrals

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The discussion focuses on finding Cauchy principal values for divergent integrals, contrasting with the more common examples of convergent integrals where the principal value equals the integral's value. The user expresses difficulty in locating resources or examples specifically addressing divergent integrals. They provide two specific integrals as examples for which they seek solutions. Ultimately, the user indicates they have resolved their queries and offers to share their solutions with others.
saybrook1
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Homework Statement


So I've found a ton of examples that show you how to find cauchy principal values of convergent integrals because it is just equal to the value of that integral and you prove that the semi-circle contribution goes to zero. However, I need to find some Cauchy principal values of divergent integrals and I can't find any examples or even problems in any books that have these. Perhaps I'm just looking in the wrong place I'm not sure. If anyone could point me in the direction of any examples where principal values are found of divergent integrals that would be amazing, thank you.

Homework Equations


P.V. \int^{\infty}_{-\infty}\frac{sin2xdx}{x+4}
P.V.\int^{\infty}_{-\infty}\frac{cos2xdx}{x^{2}-16}

The Attempt at a Solution


I've gone through many examples but they just prove that the contribution of the arc on the contour goes to zero and so the principal value equals the value of the convergent integral. Any examples resembling my problems would be great.[/B]
 
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Figured them out, if anyone wants the solutions let me know.
 
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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