Fun with series 2
Algebra
Level
4
The value of
\(\dfrac{2}{1\times2\times3}-\dfrac{2}{2\times3\times4}-\cdots-\dfrac{2}{19\times20\times21}-\dfrac{2}{20\times21\times22}\)
is \(\dfrac{m}{n}\) where \(m\) and \(n\) are co-prime. Find \(m+n\).
by
Tom Zhou