Binomial theorem for positive integers
The binomial theorem for positive integers can be expressed as
(x + y)n = xn + n xn-1 y + n ((n - 1) / 2!) xn-2 y2 + n ((n - 1)(n - 2) / 3!) xn-3 y3 + .... + n x yn-1 + yn (1)
In mathematics the binomial theorem is important as an equation for expansion of powers of sums.