Question

Which counterexample disproves the conjecture? If n is a positive integer, then 2^n-1 is a prime number

Answer 1

n=6
5
3
2

Answer 2

are the rest of those like A. n=6 B. n=5 C. n=3 D. n=2?

Answer 3

yes... i did it the short way srry lol

Answer 4

Aight B is a counter example because 2(5) - 1 = 10 - 1 = 9 is NOT a prime number.

Answer 5

replace n by the given choices and see what the values are

Answer 6

So n=5 would be your answer.

Answer 7

No Chris its 2 to the power n not 2 times n.

Answer 8

last one 2 is 2^2 - 1 = 4-1 = 3 which is a prime number so 2 is not a counterexample.

Answer 9

Opp my mistake, you right.