Lotka-Volterra competition equations For each case, derive the equations for all nullclines of the Lotka-Volterra model in Example 1 and use them to construct the phase plane, including all nullclines, equilibria, and arrows indicating the direction of movement. (Assume that all constants are positive.)

(a) K1 . K2 and K2 , K1

(b) K1 , K2 and K2 . K1

(c) K1 , K2 and K2 , K1

(d) K1 . K2 and K2 . K1