P(n):2n<n! P(1),P(2),P(3) are not true. P(4):16<24 is true P(K):K!>2K is true for some K∈N,K>4
To prove P(K+1):(K+1)!>2K+1 is true
Multiplying both sides of P(K) by (K+1), we get, (K+1)!>2K(K+1)>2K.2(asK>4)
Hence by Principle of Mathematical induction, P(n) is true ∀n∈N,n≥4