Question

Which of the following uses set builder notation to denote the set of all real numbers that are either less than 0 or greater than 20?

a) {x∈R∣x<0 or x>20}
b) {x∈R∣x>0 or x<20}
c) {x∈R∣x<0 and x>20}
d) {x∈R∣x>0 and x<20}

Answer 1

The set of all real numbers that are either less than 0 or greater than 20 can be denoted using set builder notation as x<0 or x>20.

Step-by-step explanation:

Set builder notation is used to describe a set of elements using specific criteria. In this case, we want to describe the set of all real numbers that are either less than 0 or greater than 20. The correct set builder notation for this set is option a) x∈R. This notation states that x is an element of the set of real numbers, denoted by R, and x is less than 0 or x is greater than 20.