O ozidolroks Member Joined Feb 26, 2008 Messages 36 Gender Female HSC 2009 Jul 11, 2009 #1 why is n-1 (choose) (k-1) = (n-1)(n-2)... (n-k+1)/ 1x2x3x4...x(k-1)
Trebla Administrator Administrator Joined Feb 16, 2005 Messages 8,401 Gender Male HSC 2006 Jul 11, 2009 #2