1. Prove that: v(t) = (y(t+Δt) - y(t-Δt))/2Δt using kinematic equations for constant acceleration. 3. I tried using the limit as Δt approaches 0 of (y(t+Δt)-y(t))/Δt and somehow adding to get Δt. Could I manipulate the kinematic equations somehow by setting t equal to (t+Δt) or (t-Δt)?