A proof of the identity $$1+2+\cdots + (n-1) = \binom{n}{2}$$
(Adapted from an entry I saw at Wolfram DemostrationsDemonstrations)
|
2 | corrected spelling | ||
|
|
||||
|
Post Made Community Wiki by Anton Geraschenko♦♦
|
||||
|
|
||||
|
|
1 |
|
||
|
A proof of the identity $$1+2+\cdots + (n-1) = \binom{n}{2}$$
(Adapted from an entry I saw at Wolfram Demostrations) |
||||
