The correct symbol for interval notation when a value is to be included in the solution is Parenthesis or Brackets.
Option A and C is correct.
An interval notation is used to demonstrate that a value lies between two endpoints. Intervals are denoted by rectangular brackets or parentheses, and the two numbers can be separated by a comma. The number value on the left represents the smallest element or lower limit. The number value on the right represents the highest element or upper limit.
For example;
We can represent the inequality -6 ≤ x ≤ 2 in interval notation as [-6,2]
Therefore, we can conclude that the correct symbol for interval notation when a value is to be included in the solution is Parenthesis or Brackets.
Learn more about interval notation here:
