In combinatorics, the expression (n 0) equals 1 because it represents the number of ways to choose 0 elements from a set of n elements, which is always one way—by choosing nothing. This is defined using binomial coefficients, expressed mathematically as \binom{n}{k}=\frac{n!}{k!(n-k)!}. The confusion often arises because this notation is not commonly used in high school math curricula. The convention that 0! equals 1 is crucial to understanding this concept. Overall, the topic highlights the importance of binomial coefficients in combinatorial mathematics.
