Question

4^n+15n-1 is divißible bit 9​

Answer 1

Answer:

the answer i 134 pie r ok

Answer 2

P(n):4n

+15n−1 is a multiple of 9 for any natural number n.

4n

can be written as (1+3)n

whose binomial expansion gives :

1+3n+9(n C2 )+........+3n+15n−1

which reduces to :

18n+9(n C2 )+........+3n

=9k where k is an integer.

Therefore,

4n +15n−1 is divisible by 9.

Hope it helps.