Is anybody here acquainted with the De Moivre-Jordan Theorem?
Cannot locate anything on the internet, so here I shall reproduce a rather terse account of it from a textbook on Fundamental Probability:
For events the probability that exactly m of the occur, m = 0, 1, . . . , n, is given by
Given n=4, m=2, calculate the probability that exactly 2 out of 4
is given by:
Looks like its something to do with the double counting like the inclusion-exclusion theory, but cannot figure it out.
Can anyone link me to the correct wiki page or try to explain to me what is happening here?