Question

1) What universal set would you propose for each of the following

a) The set of all circles of radius one unit in a plane

b) The set of all natural numbers

c) The set of all even integers.

d) The set of all isosceles right angled triangle.

2) Write all the proper subsets of the set {-1,3,4}. Also write those proper subsets which are superset of the set {3}.

Answer 1

(1)

a) Set of all circles in a plane

b) The set of all whole numbers

c) The set of all integers

d) The set of all triangles

(2) a) {–1, 3}, {–1, 4}, {3, 4}, {–1}, {3}, {4}

b) {–1, 3, 4}, {–1, 3}, {3, 4}