Question

(2^3n-1) is a multiple of 7.​

Answer 1

Answer:

2^(3n) - 1

= 2^(3n) - 1^n

= 8^n - 1^n

= (8-1)(8^(n-1) + .....+ 1)

= 7 x Some Integer

This is divisible by 7

Answer 2

(2^3n -1) is a multiple of 7


True


Hope it helps you