Tracey M. answered • 07/01/18

BBA in Actuarial Science ,33+ years as math tutor, Assoc Sociey of Act

When a bracket is used, you include that value in the interval

So the interval [2,8] is all the numbers between 2 and 8 inclusive (2 and 8 are possible values)

When a parentheses is used, you do not include that value in the interval

The interval (1,9) is all the numbers between 1 and 9 exclusive, (1 and 9 are not possible values)

Your question:

[2,infinity) means all numbers greater than or equal to 2 up to to infinity

(1, infinity) means all numbers greater than 1 to infinity

hope this helps

Zainab J.

07/01/18