Hi Arun,

Roster form means writing a set with all its elements.

Example - 

A = {x: x is an integer and –3 < x < 7}

Represent A in roster form.

So, we find all elements of set A

We know that

Integers = ......-4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10….

The elements of this set are –2, –1, 0, 1, 2, 3, 4, 5, and 6 only.

Thus, set A in roster form is A = {–2, –1, 0, 1, 2, 3, 4, 5, 6}