A problem for a friend II
Algebra
Level
3
The roots of \(x^{2016}-x^{2015}+x^{2013}-x^{2010}+x^{2006}-\ldots-1 = 0\) are \(r_{1}, r_{2}, \ldots, r_{2016}\).
Find
\[\sum_{1 \leq i < j \leq 2016} r_{i}r_{j}\]
by
Jake Lai