number 22

In Exercises 1324, use propositional logic to prove that the argument is valid. Section 1.2 Propositional Logic D ) 18. [A ( B C)]^(A V D') AB( DC ) 19. (A' B')^B^ (A C)C 20. (A B) A[B ( C D )] ^ [A (B C)] ( A 21. [A + (B +C)] [B + (A C)] 22. (A AB) (A B')' 23. (A C) A(C B') ABA' 24. [A (BVC)] AC' (A + B)