Question

What does 'n' and 'e' represent in this set? Please solve this equation (Or whatever it is)

Answer 1

that statement is read as..

X belongs to Natural Number N..

for example 5(a) {1,2,3,4,5.....,98,99} finite set

Answer 2

N represents natural number and E is the sign of 'belongs to'

For instance, 5a can be read as 'A is the set of all x such that x belongs to natural number and x is smaller than 100'