Alpha Beta pruning results in the same answer as classical Minimax search.
Alpha Beta pruning is an optimization: there's no need to search the whole tree to know that a branch can be pruned (but still result in the same answer as minimax).
Minimax with Alpha Beta pruning gives you the best position for a given depth. ("Best" as defined by Minimax to the same depth without pruning).
Alpha Beta pruning is an optimization: there's no need to search the whole tree to know that a branch can be pruned (but still result in the same answer as minimax).
Minimax with Alpha Beta pruning gives you the best position for a given depth. ("Best" as defined by Minimax to the same depth without pruning).