Question

let n be an odd integer. Assume that a is an integer such that a=2(modn) show that gcd(a,n) = 1

Answer 1

Tell me if I'm close.
n| a -2
a-2 = nq+0
a = nq+2
-->
n=2q+r 0<r<2

Answer 2

hmm, a few examples might help

5 = 2 mod(3)
6 = 2 mod(4); but gcd (4,6) = 2

Answer 3

let n be odd, helps if i read the whole thing

Answer 4

of course, of a and n are even, there are gonna have a gcd of at least 2

Answer 5

2 cases, let a = 2k, and let a = 2k+1, such that n=2m+1 is an idea

Answer 6

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