**(i) **Given that,

A = {3, 6, 9, 12, 15, 18, 21}, B = {4, 8, 12, 16, 20},

C = {2, 4, 6, 8, 10, 12, 14, 16}, D = {5, 10, 15, 20}

To find, A−B

The difference of the sets A and B in this order is the set of elements which belong to A but not to B.

A − B = {3, 6, 9, 12, 15, 18, 21} - {4, 8, 12, 16, 20}

A – B = {3, 6, 9, 15, 18, 21}

**(ii)** To find, A−C

The difference of the sets A and B in this order is the set of elements which belong to A but not to B.

A − C = {3, 6, 9, 12, 15, 18, 21} - {2, 4, 6, 8, 10, 12, 14, 16}

A – C = {3, 9, 15, 18, 21}

**(iii)** To find, A−D

The difference of the sets A and B in this order is the set of elements which belong to A but not to B.

A − D = {3, 6, 9, 12, 15, 18, 21} - {5, 10, 15, 20}

A – D = {3, 6, 9, 12, 18, 21}

**(iv)** To find, B−A

B− A = {4, 8, 12, 16, 20} - {3, 6, 9, 12, 15, 18, 21}

B – A = {4, 8, 16, 20}

**(v)** To find, C−A

C − A = {2, 4, 6, 8, 10, 12, 14, 16} - {3, 6, 9, 12, 15, 18, 21}

C – A = {2, 4, 8, 10, 14, 16}

Answered by Pragya Singh | 2 years agoFind the symmetric difference A Δ B, when A = {1, 2, 3} and B = {3, 4, 5}.