Set Operations

Set Operations
OPERATIONS ON SETS:

1. UNION OF SET- the union of A and B, denoted by A∪ B, is the set of all elements
in x in U such that x is in A or x is in B.
2. INTERSECTION OF SET - the intersection of A and B, denoted by A ∩ B, is the set
of all elements in x in U such that x is in A and x is in B.

Given: A= { a, b, c }
B = { c, d, e }
C = { f, g }
D = { f, g, h, i}
Let us answer the set of examples:

a. A ∪ B = { a , b, c, d, e} d. A ∩ B = { c ]
b. C ∪ D = { f , g, h, i } e. C ∩ D = { f, g }
c. B ∪ C = { c, d, e, f, g } f. B ∩ C = { }

3. COMPLEMENT OF SET- The complement of a set or absolute complement A,
denoted by A' , is the set of all elements in x in U such that x is not in A.
Given: A={ a, b, c }
B= { c, d, e }
U = { a, b, c, d, e, f, g, h }
Find the following:

a. A' = { d, e, f, g, h} c.(A∩B)
′={a,b,d,e,f,g,h}(A∩B)′={a,b,d,e,f,g,h}(( A ∩ B ) ′ = { a , b , d , e , f , g , h }(( A
∩B)′={a,b,d,e,f,g,h}'
b. B' = { a , b, f, g, h } d.(A' ∩ B' ) ={ f, g, h}

4. DIFFERENCE OF SET - The difference of A and B ( or relative complement of B with
respect to A) , denoted by A - B, is the set of all elements x in U such that x is in A and
x is not in B.
Given: A={ a, b, c }
B = { c, d, e }