👉 The complemental of a set A is defined as the set of all elements in A that are not in A. In other words, it is the set of all elements that are not in the original set but are contained within it. For example, if we have a set S = {1, 2, 3, 4}, then its complemental would be {3, 4}. The complemental of a set can also be used to find out how many elements are