game theory

Equilibrium in a Repeated Game. Consider the simultaneous move stage game H L H 1, 1 -1, 110 L 110, -1 0, 0 which is played repeatedly for infinitely many periods. Consider the "grim trigger" strategy of playing H in period one; playing H as long as both players have always played H in the past, and playing L otherwise. For what values of the common discount factor, o, do these strategies satisfy subgame perfection