Posts Tagged ‘method’

Today, I decided to post a very eye-catching method for calculating an integral which shows very often in Statistical Mechanics in Physics.
Let’s try to calc this
First let’s mark it with a name , then

What is just a double integral over the whole 2d surface. It can be also written in polar coordinate system as [...]


Lets calculate more compilated sum

further, the last one equals to and now the first of the sums is equal to however the second one is easy, cause its a geometric sequence equal to under the law from previous post. Now we have , in the result of elementary algebraic transformation we [...]


Asume that we want to calculate

Of course,
But the sum on the right side is equal to Therefore and so,