Epsilon Reformed Defintion Let a,b∈R Suppose a<b Suppose f(x) is bounded on [a,b] ∀ϵ>0,∃ Partition P on [a,b] s.t U(f,P)−L(f,P)<ϵ This is more user friendly since all you need to do is pick a partition which has an upper darboux sum equal to the lower darboux sum