Sea δ=ϵ\delta=\epsilonδ=ϵ. Si 0<∣x−3∣<ϵ0 < |x-3| < \epsilon0<∣x−3∣<ϵ, entonces ∣x+3−6∣=∣x−3∣<ϵ|x+3-6|=|x-3| <\epsilon∣x+3−6∣=∣x−3∣<ϵ.