Let given statement is P(n) where n ∈ N i.e.,
Hence, 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, given statement is also true for n = m + 1,
i.e., P(m + 1) is true.
Hence Proved.