If P(n) is the statement “2n ≥ 3n”, and if P(r) is true, prove that P(r + 1) is true.
Given. P(n) = “2n ≥ 3n” and p(r) is true.
Prove. P(r + 1) is true
we have P(n) = 2n ≥ 3n
Since, P(r) is true So,
= 2r≥ 3r
Now, Multiply both side by 2
= 2.2r≥ 3r.2
= 2r + 1≥ 6r
= 2r + 1≥ 3r + 3r [since 3r>3 = 3r + 3r≥3 + 3r]
Therefore 2r + 1≥ 3(r + 1)
Hence, P(r + 1) is true.