Binomial Theorem

The binomial theorem for positive integers can be expressed as

(x + y)ⁿ = xⁿ + n x^n-1y + n ((n - 1) / 2!) x^n-2 y² + n ((n - 1)(n - 2) / 3!) x^n-3 y³ + .... + n x y^n-1 + yⁿ                 (1)

In mathematics the binomial theorem is important as an equation for expansion of powers of sums.