If A and B are two sets taken from some universe U, then the intersection of A and B written A ½ B, is the set containing all elements common to sets A and B.
A ½ B = { X \ (X · A) ^(X
· B)}
Example.
A = { 1,2,4}
B = { 2,4,6,7}
A ½ B = { 2,4}
Note: The definition for intersection says that in order for an element to be part of the solution set for A ½ B it must be both an element of A and an element B. The definition of the conjunction “and” also requires that both statements, p and q be true.