<p>I'm not kidding you.
[quote]
There are two ways of proving that lim S<em>n=pi^2/6
[/quote]
Limit as x approaches what? ∞?
[quote]
consider f(x)=1/x^2, and write S</em>n as \integral_1^n f(x)dx
[/quote]
Well you are basically integrating 1/x² which is not my question. I'm asking for a discrete sum (x = positive integers) rather than an integral. If you integrate wrt x, from 1 to n, n will assume all values in between, say, 1 and 2...</p>
<p>same with method #1</p>