first problem:
If x=a (mod n), prove that either x=a (mod 2n) or x=a+n (mod 2n).
dont really know where to begin.
second problem:
If p and q are distinct primes, prove that
p[sup:3hgk2h56]q-1[/sup:3hgk2h56] + q[sup:3hgk2h56]p-1[/sup:3hgk2h56] = 1 (mod pq)
If x=a (mod n), prove that either x=a (mod 2n) or x=a+n (mod 2n).
dont really know where to begin.
second problem:
If p and q are distinct primes, prove that
p[sup:3hgk2h56]q-1[/sup:3hgk2h56] + q[sup:3hgk2h56]p-1[/sup:3hgk2h56] = 1 (mod pq)