Results 1 to 3 of 3

Math Help - Combinations

  1. #1
    Newbie
    Joined
    Aug 2009
    Posts
    8

    Question Combinations

    This is a little complicated, i'll try to explain as best i can.

    Say I have n different numbers,
    I wish to find the summation of every possible way of multiplying different numbers together.

    For clarification: if I would want:

    If i would want:


    Basically, I just need a function that gives this result.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Member courteous's Avatar
    Joined
    Aug 2008
    From
    big slice of heaven
    Posts
    206
    Choosing x elements out of set of n elements ( z_1, ..., z_n) and disregarding their order is the definition of combinations.

    F(x, z_1, ..., z_n) = \frac{n(n-1)...(n-x+1)}{x!}=\frac{n!}{(n-x)!x!}={n \choose x}
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Aug 2009
    Posts
    8
    Except you obviously haven't read my post at all. That's not what I'm after. I'm fairly sure I explained what I'm looking for fairly clearly.
    Ok, you've shown how many different terms the function will have in terms of x and n. It isn't a formula that will calculate the value of each term and add them together.

    Could somebody please read my post and help me with this?
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Combinations in a set
    Posted in the Discrete Math Forum
    Replies: 3
    Last Post: September 9th 2010, 06:19 AM
  2. How many combinations are possible?
    Posted in the Discrete Math Forum
    Replies: 0
    Last Post: July 23rd 2009, 07:53 PM
  3. Combinations
    Posted in the Statistics Forum
    Replies: 2
    Last Post: May 5th 2008, 08:28 AM
  4. How many combinations..?
    Posted in the Algebra Forum
    Replies: 9
    Last Post: May 2nd 2008, 10:34 AM
  5. combinations
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: April 27th 2008, 09:00 AM

Search Tags


/mathhelpforum @mathhelpforum