For a discrete uniform distribution on {1,2,…,n}\{1, 2, \dots, n\}{1,2,…,n}, what is the variance?
n2−112\frac{n^2 - 1}{12}12n2−1
n(n+1)2\frac{n(n+1)}{2}2n(n+1)
n−112\frac{n-1}{12}12n−1
n2n^2n2