A×C={(1,a),(1,b),(1,c),(2,a)2(2,b),(2, c)} A×A={(1,1),(1,2),(2,1),(2,2)}。 A×=×A=8 Definition 2.4: LetA,A..a be sets. The Cartesian product of A142…An denoted A1×A2×…XAn, is the set of all ordered n-tuples(a1,a2,.ga,)where aEA: for i=1.2...n. Hence A1×A2×…×An={(a1a2,…,n)a∈A ,i=1,2,,n}A×C={(1,a),(1,b),(1,c),(2,a),(2,b),(2, c)}; A×A={(1,1),(1,2),(2,1),(2,2)}。 A×=×A= Definition 2.4: Let A1 ,A2 ,…An be sets. The Cartesian product of A1 ,A2 ,…An , denoted by A1×A2×…×An , is the set of all ordered n-tuples (a1 ,a2 ,…,an ) where aiAi for i=1,2,…n. Hence A1×A2×…×An ={(a1 ,a2 ,…,an )|aiAi ,i=1,2,…,n}