∀ n ϵ N, P(n):4.7n+20 is divisible by 24. State true or false.
True
P(n):4.7n+20 is divisible by 24
P(1):28+20=48→divisible by 24P(k):4.7k+20 is divisible by 24→assume true⇒4.7k+20=24qNow, 4.7k+1+20=7.(4.7k)+20=6.4.7k+(4.7k+20)=24.7k+24qP(k+1) is true
∴P(n) is true4.7n+20 is divisible by 24