note that it is an odd function ( a fantastic odd function )
I haven't checked the details here but care must be taken with improper integrals of this type. An odd integrand does not mean that an improper integral of this type is equal to zero. It could be divergent. A case in point is ....
I haven't checked the details here but care must be taken with improper integrals of this type. An odd integrand does not mean that an improper integral of this type is equal to zero. It could be divergent. A case in point is ....
Oh , I didn't realise this ... but luckily this integral mentioned above is convergent.