Suppose that A, B, and C are sets. Prove or disprove that (A ? B)?C = (A ?C) ? B.

Solution:Step 1: Suppose that A, B, and C are sets. Assume A={2,4,6,8,10}-even number set B={1,3,5,7,9}-odd number set C={1,2,3,4,5}-positive real number set Step 2: We have to prove or disprove that (A B)C = (A C) B.Step 3: This statement is true. (A B)C = (A C) B. A-B-C=A-C-B A-B-C=A-B-C We take an example to prove this statement.