Help Solving Integral: pi*(1-1/e)

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In summary, the person is seeking help with an integral and has reached an incorrect answer of -pi/e. Another person suggests using complex analysis to solve the integral and asks for clarification on the steps taken. The original person thanks them for the help and the conversation is moved to a more appropriate forum.
  • #1
gholamghar
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please Help for this integral!

hello
could anyone help me for this integral:
107422924.XHIPuDo7.integral.jpg


every time i solve this i reach to this answer: -pi/e

but the right answer is :pi*(1-1/e)
 

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  • #2


How about showing us HOW you got that result? I think I would be inclined to integrate around a loop in the complex plane- integrate from -R to R on the real line, then counter-clockwise around the half circle in the positive i half plane with radius R. The function has a pole at z= i. (And a removable discontinuity at z= 0.) Then, of course, take the limit as R goes to infinity. Since the integrand obviously goes to 0 as |z| goes to infinity, the integral depends completely on the residue at z= 1. Did you calculate the residue?

But that might be exactly what you are trying to do or it might be completely different. What, if anything, you did wrong, we can't say until we see what you did.

And since this does not have anything, directly, to do with "differential equations", I am moving it to "Calculus and Analysis".
 
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  • #3


thanks for the answer,it helped a lot
 

1. What is the concept behind solving integrals?

The concept behind solving integrals is finding the area under a curve. Integrals are used to calculate various quantities such as distance, volume, and probability in mathematics and science.

2. What does the "pi*(1-1/e)" represent in the integral?

The "pi*(1-1/e)" represents the function that needs to be integrated. In this case, it is a function that involves the mathematical constant pi and the natural logarithm constant e.

3. How do I solve the integral "pi*(1-1/e)"?

To solve this integral, you can use various techniques such as substitution, integration by parts, or the use of trigonometric identities. You can also use online integral calculators or consult a math tutor for assistance.

4. What is the significance of the constant pi in this integral?

The constant pi represents the ratio of a circle's circumference to its diameter and is commonly used in many mathematical formulas involving circles and curves. In this integral, it is used to calculate the area under the curve.

5. Can I use the solution to "pi*(1-1/e)" for other integrals?

No, the solution to this specific integral cannot be used for other integrals as each integral has its unique function and limits of integration. However, the techniques used to solve this integral may be applicable to other integrals as well.

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