Question

If A = {1,2,3,4} , B = {3,4,5,6,} and C = {1,2,4,6,7} , then find A U B ​

Answer 1

Solution:-

Given :-

=> A = { 1 , 2 , 3 , 4 }

=> B = { 3 , 4 , 5 , 6 }

=> C = { 1 , 2 , 4 , 6 , 8 }

To find

:- A U B

Now

=> A = { 1 , 2 , 3 , 4 } , B = { 3 , 4 , 5 , 6 }

=> A U B = { X : X ∈ A and X ∈ B }

=> { 1 , 2 , 3 , 4 , 5 , 6 }

Answer:-

A U B = { 1 , 2 , 3 , 4 , 5 , 6 }

Some laws of Algebra of sets

(i) Associative Law

• ( A U B ) U C = A U ( B U C )

• ( A ∩ B ) ∩ C = A ∩ ( B ∩ C )

(ii) Commutative Law

• A ∩ B = B ∩ A

• A U B = B U A

(iii) Idempotent Law

• A ∩ A = A

• A U A = A

(iv) Law of Universal set

• A ∩ U = A

• A U U = U