give a short argument thta the complexity class P is closed under cartesian product, that is $,$ if A and B are languages in P$,$ then AxB would be in P also. Hint if the language A and B were in P$,$ both their decider TMs would function in polynomial time. A decider for AxB could be constructed from the deciders for A and B by running each one to decide if the components of an ordered pair $($a$,$b$)$ in AxB are, in fact, in A and B$,$ respectively