Question

Which of the following numbers will completely divide (49¹⁵ -1)?

Options

• 8

• 14

• 48

• 50

Answer 1

8

Explanation

(xⁿ -1) will be divisible by (x + 1)
∴ when n is even.

(49¹⁵ -1) = {(7²)¹⁵ -1} = (7³⁰ -1), is divisible by (7+ 1),

i.e. 8.