I have some questions about the search functions in artificial intelligence that I cannot understand. I know that Uniform-cost search is a special case of the A* search algorithm if its heuristic is a constant function. Also I know that Breadth-first search (BFS) is a special case of A* when all edge costs are positive and identical. Best-first search is also a special case of A* search. But ho can I show that? How can I prove that all the above are correct?