Let n be any counting number. Using the two questions above as a guide, how

Question

many subsets does the set {1,2,3,...,n−1,n} have? Prove it as well.
First question:Including itself, how many subsets does the set {1, 2, 3} have? List them.
Second Question: Including itself, how many subsets does the set {1, 2, 3, 4} have? List them.

Answer 1

This is called the power set.Any set of n elements has 2^n subsets.

Just sum all the powers of 2 from 0 to n-1