Let J be the ring of integers, p a prime number, and () the ideal of...
3. If the integers mi, i = 1,..., n, are relatively prime in pairs, and a1,..., an are arbitrary integers, show that there is an integer a such that a = ai mod mi for all i, and that any two such integers are congruent modulo mi ... mn. 4. If the integers mi, i = 1,..., n, are relatively prime in pairs and m = mi...mn, show that there is a ring isomorphism between Zm and the direct product...
7.23 Theorem. Let p be a prime congruent to 3 modulo 4. Let a be a natural number with 1 a< p-1. Then a is a quadrutic residue modulo pif and only ifp-a is a quadratic non-residue modulo p. 7.24 Theorem. Let p be a prime of the form p odd prime. Then p 3 (mod 4). 241 where q is an The next theorem describes the symmetry between primitive roots and quadratic residues for primes arising from odd Sophie...
Let p be a prime number. Prove that if there exists a solution to the congruence c(mod p), then there exist integers m, n such that p = m2 + 2n2. Hint. Make a careful study of the proof of Fermat's Two Square Theorem, and then try to modify that proof (or at least some portion of it) to come up with a proof of this statement. Toward the end of the proof, the following observation can be helpful: If...
Question 6 (optional) For positive integers p 2 2, Wilson's Theorem states that p is a prime if and only if (p-1)!-1 (mod p) (a) Prove Wilson's Theorem (b) Discuss whether Wilson's Theorem is suitable as a primality test for finding primes to use with RSA. Question 6 (optional) For positive integers p 2 2, Wilson's Theorem states that p is a prime if and only if (p-1)!-1 (mod p) (a) Prove Wilson's Theorem (b) Discuss whether Wilson's Theorem is...
ame: . (10 points) Let p > 3 be any prime number. (a) Show that p mod 6 is equal to 1 or 5 (b) Use part (a) to prove that pe - 1 is always a multiple of 24.
Please solve all questions 1. Let 0 : Z/9Z+Z/12Z be the map 6(x + 9Z) = 4.+ 12Z (a) Prove that o is a ring homomorphism. Note: You must first show that o is well-defined (b) Is o injective? explain (c) Is o surjective? explain 2. In Z, let I = (3) and J = (18). Show that the group I/J is isomorphic to the group Z6 but that the ring I/J is not ring-isomorphic to the ring Z6. 3....
27. (a) Let m and n be integers > 1 which are relatively prime. Show that the map f : Z → Z/mZ × Z/nZ whith f(x) = (x + mZ, x + nZ) is surjective (b) Prove the Chinese Remainder Theorem: If m and n are relatively prime integers > 1 and if a and b are any integers, then there exists a E Z such that b(mod n). a(mod m) and a a Hint: (a)] 27. (a) Let...
Let R be a commutative ring with unity. If I is a prime ideal of R, prove that I[x] is a prime ideal of R[x].
8. Let p be a prime number. Define -c0t}cQ ZAp) Prove that Zp) is a subring of Q Prove that Z is a subring of Z Show that the field of fractions of Zp) is isomorphic to Q
Problem 2 (Chinese Remaindering Theorem) [20 marks/ Let m and n be two relatively prime integers. Let s,t E Z be such that sm+tn The Chinese Remaindering Theorem states that for every a, b E Z there exists c E Z such that r a mod m (Va E Z) b mod nmod mn (3) where a convenient c is given by 1. Prove that the above c satisfies both ca mod m and cb mod n 2. LetxEZ. Prove...