Discrete mathematics

4. Let X = {1,2,3} and Y = {a,b,c,d}. List the elements in the set Y X. (2 points)

5. Answer true of false. (1 point each)

(a) {x} {x}

(b) {x} {x}

(c) {x} {x, {x}}

(d) {x} {x, {x}}

(e) {2} P({1,2})

(f) {2} P({1, 2})

6. List the members of P({a, b, c, d}). Which are proper subsets of {a, b, c, d}? (5 points)

7. Write the truth table of the proposition (p q) (q r). (5 points)