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MAMLSTEN INTEGRALS - PART II

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In continuation of our previous post about Malmsten integrals , we will today prove the following four integrals: For the First Integral Where We used Vardi´s integral: and that To evaluate the second integral, we first consider the following integral If we differentiate the above result w.r. to we obtain Letting Then to compute our integral Where we used that (1) Differentiating     w.r. to (2) We have also previously proved here that (3) and (4) Setting in (1) and (2) we get For the third integral, recall the previous established result If we let   , then For the last integral let in Then Where we used the reflection formula To write

INTEGRAL ln x/cosh^2 x \,dx

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In this post We will prove the following integral Lets first evaluate the integral (1) Differentiating (1) w.r. to s Now, letting (2) Now recall that (3) And consequently (4) We also have the following relations ( proved here ) and Setting in (3) and (4) we get (5) (6) Plugging (5) and (6) in (2) Appendix Recall the geometric series

MAMLSTEN INTEGRALS - PART I

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We will today prove the following integral that belongs to a family of log-log integrals known as Malmsten integrals  which Vardi´s integral is a particular case: Mamlsten Integrals (1) If we let      in (1) we obtain the desired result: (2) Appendix: Cauchy Product Example We have that and , we therefore obtain Evaluation of the integral: Recall the sine of a difference formula And The Fourier series for the LogGamma function proved here If we let       We obtain Or