Let A be a nonempty subset of R Let I(A) denote the set of interior po...
Explanation:
To understand why option 'A' is the correct answer, let's first define what interior points are.
Definition: A point x is said to be an interior point of a set A if there exists an open interval containing x that is entirely contained in A.
Now, let's consider the given nonempty subset A of the real numbers.
Case 1: A has no interior points
If A has no interior points, it means that for every point x in A, there is no open interval containing x that is entirely contained in A. In other words, every point in A is either on the boundary of A or outside of A. In this case, the set I(A) of interior points will be empty.
Case 2: A has at least one interior point
If A has at least one interior point, it means that there exists a point x in A such that there is an open interval containing x that is entirely contained in A. In this case, the set I(A) of interior points will contain at least one element.
Since the question states that A is a nonempty subset of R, it implies that A must have at least one element. Therefore, it is possible for A to have interior points, and thus option 'A' is correct.
Summary:
In summary, the set of interior points I(A) can be empty if A has no interior points. However, if A has at least one interior point, then the set I(A) will contain at least one element. Therefore, the correct answer is option 'A'.
Let A be a nonempty subset of R Let I(A) denote the set of interior po...
Empty, Since if a set contains an interior point, infact it contains infinitely many interior points