I should be writing math textbooks. What does anyone use this particular equality for?
On 10/30/05, Mathieu Bouchard matju@artengine.ca wrote:
On Sat, 29 Oct 2005, Chuckk Hubbard wrote:
Just a note, I came up with a pretty obvious proof for: SUM (k=0 to N-1) i^k = (i^N - 1) / (i - 1) (i - 1) (i^0 + i^1 + i^2 + .... + i^(N-1)) = -i^0 + i^1 - i^1 + i^2 - i^2 ... + i^(N-1) - i^(N-1) + i^N = i^N - 1 All the terms cancel except the lowest and highest powers of i.
That's the same proof that is used in all math textbooks.
Mathieu Bouchard - tél:+1.514.383.3801 - http://artengine.ca/matju Freelance Digital Arts Engineer, Montréal QC Canada
-- "It is not when truth is dirty, but when it is shallow, that the lover of knowledge is reluctant to step into its waters." -Friedrich Nietzsche, "Thus Spoke Zarathustra"