The problem of determining the value of $\zeta (2)$ also known as t...
Tom Mike Apostol was an American analytic number theorist and profe...
Note that $\int_{0}^{1} x^n dx= \left[ \frac{x^{n+1}}{n+1}\right]_{... With this change of variables we change the region and limits of in... Alternatively we could note that$\$ \frac{d}{du} \arctan \frac{...