If A = {x : x is natural number}, B = {x: x is an even natural number}

1.	If A = {x : x is natural number}, B = {x: x is an even natural number}, C = {x, x is an odd natural number}, then find A ∩ B, A ∩ C, A – B, A – C and describe sets in set builder form.
Answer» A = {1, 2, 3, 4, ………….} B = {2,4, 6, 8, ………….. }; C = {1,3,5,7, ………….. } For finding, A∩B = {1,2,3,4, } ∩ {2,4,6,8, …. } = {2, 4, 6, 8…………. } = {x/x is an even natural number} For finding, A ∩ C = {1,2,3,4,…….} ∩ {1,3,5,7, ………. } = {1,3,5,7 :…….} A = {x/x is an odd natural number} For finding, A – B = {1,2,3,4, ……….. } – {2,4,6,8, …………… } = {1,3,5, ………….. } = {x/x is an odd natural number} For finding A – C = {1,2,3,4,…….}-{1,3,5,7, } = {2,4,6,8, ,…} = {x/x is an even natural number}

If A = {x : x is natural number}, B = {x: x is an even natural number}, C = {x, x is an odd natural number}, then find A ∩ B, A ∩ C, A – B, A – C and describe sets in set builder form.

Answer»

A = {1, 2, 3, 4, ………….}

B = {2,4, 6, 8, ………….. };

C = {1,3,5,7, ………….. }

For finding,

A∩B = {1,2,3,4, } ∩ {2,4,6,8, …. }

= {2, 4, 6, 8…………. }

= {x/x is an even natural number}

For finding,

A ∩ C = {1,2,3,4,…….} ∩ {1,3,5,7, ………. }

= {1,3,5,7 :…….}

A = {x/x is an odd natural number}

For finding,

A – B = {1,2,3,4, ……….. } – {2,4,6,8, …………… }

= {1,3,5, ………….. }

= {x/x is an odd natural number}

For finding

A – C = {1,2,3,4,…….}-{1,3,5,7, }

= {2,4,6,8, ,…}

= {x/x is an even natural number}