1. Let p be a prime. Show that the equation x^2 'is congruent to' 1 mod p has exactly two solutions in Zp, 1 and p - 1.
2. Consider Z13 = {1, 2, ..., 12}. The elements 2, 3, ..., 11 can be paried off with their inverses as follows
(2, 7), (3, 9), (4, 10), (5, 8), (6, 11)
Problem : Generalize this example to the case where p is any prime and show that
(p - 1)! 'is congruent to' -1 mod p
(This result is called Wilson's theorem).
3. Show that if p is prime
(p - 1)(p - 2) ... (p - r) 'is congruent to' (-1)^(r) * r! mod p
for each r = 1, 2, ..., p - 1.
4. Show that if p is prime
2(p - 3)! + 1 'is congruent to' 0 mod p
5. In 1732, Euler wrote "I derived [certain] results from the elegant theorem, of whose truth I am certain, although I have no proof : a^(n) - b^(n) is divisible by the prime n + 1 if neither a nor b is."
Use Fermat's theorem to help Euler out with a proof.
Am completely confused about all the questions - please show working! Thx
2007-05-03
16:57:57
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2 answers
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asked by
Oscar P
1
in
Mathematics