Definition: The modular multiplicative inverse of a modulo m is a number x such that (a × x) mod m = 1

Existence: MMI exists only if GCD(a, m) = 1 (a and m are coprime)

Method: Uses Extended Euclidean Algorithm to find coefficients x and y such that ax + my = GCD(a, m)

Solution: When GCD = 1, the coefficient x is the MMI (adjusted to be positive)