Elementary symmetric sum
Revision as of 13:13, 18 June 2006 by Mysmartmouth (talk | contribs)
Definition
The nth symmetric sum is the sum of a group of numbers, taken n at a time. So if the numbers are a, b, c, and d, then:
1st Symmetric Sum = a+b+c+d
2nd Symmetric Sum = ab+ac+ad+bc+bd+cd
3rd Symmetric Sum = abc+abd+acd+bcd
4th Symmetric Sum = abcd
Uses
Symmetric sums show up in Vieta's formula
