Answer and Step-by-step explanation:
The concept of the infinity introduced in extended real number system. And extended real number system define as the set of real numbers R with two symbols +∞ and -∞ having some properties . One of them is if x∈R than we have
x+(+∞)= +∞, x+(-∞)=-∞,
x-(+∞)= -∞, x-(-∞)=+∞.
