Question

If U =
{ x:x <_ 10, x ∈ N }, A = { x:x ∈ N, is prime} and B = { x:x ∈ N, x is even}. write A∩B' in roster form.

Answer 1

(a) A = {1, 4, 9, 16}

     B = {3, 6, 9, 12}

(b) C = {p, q, r, s}

     D = {a, b} 

(c) P = {x : n ∈ N, x = 3n   n< 3}

    Q = {x : x ∈ N   x < 7} 

(d) X = {x : x is a letter of the word ‘LOYAL’} 

     Y = {x : x is a letter in the word ‘FLOW’} 

(e) G = {x : x = n2, when n ∈ N} 

     H = {x : x = 4n, when n ∈ W   n < 5} 


3. If P = {1, 2, 3}   Q = {2, 3, 4}   R = {3, 4, 5}   S = {4, 5, 6}, find

(a) P ∪ Q

(b) P ∪ R