Let the given statement is P(n), where n ∈ N.
Hence, the given statement is true for n = 1,
i.e, P(1) is true.
Let given statement is true for n = m,
i.e, P(m) is true.
Hence, the given statement is also true for n = m + 1,
i.e., P(m + 1), is true.
Hence, by the principle of mathematical induction, we can say that the given statement is true for each natural number n ∈ N.
Hence Proved.