I think pilotmike is confusing prop and jet aircraft.
For a prop aircraft maximum range occurs, as Tick Tock Man said, at minimum drag speed; L/D max. When you plot the graph Drag against Airspeedthe minimum point of the graph is essentially the speed for minimum drag, however when you plot the Power Required against Airspeedgraph the tangent to the graph gives the speed for minimum drag.
For a jet aircraft maximum range occurs at 1.32 times the speed of minimum drag which in this case when you plot the Drag or Thrust Required against Airspeed occurs at the tangent to the graph.
I reckon this is correct.