12. NEZ True] [False] A maximal ideal is prime. [True] [False] The ring Q[x]/<r? + 10x...
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....
3. Consider the ring R- Zz[x] and the ideal Ixx+1>, (a) Is I a prime ideal? Is I a maximal ideal? (b) Find all the multiplicative units of R/I (a+ bx cx2 a, b, c E 2. Is the group of units cyclic? If so, give a generator. If not, determine to what commor group it is isomorphic?
QUESTION 4 (a) Let RS be a ring homomorphism with I an ideal of R and J an ideal of S. Define 0(I) = {$(1) I ET) and o-'(J) = {ve R(y) € J} and check as to whether or not (i) °(1) is an ideal of S (6) (ii) o-'() is an ideal of R (6) (Hint: I, J are two-sided ideals and in both cases of (i) and (ii) above, first check the subring conditions) (b) Given a...
Every ring in this test is commutative with 1 and 1 0 1. Which of the followings are prime ideals of Z? (Separate your answers by commas.) A. ( B. (2). C. (9). D. (111). E. (101) 2. Which of the followings are ring homomorphisms? (Separate your answers by commas.) A.φ: Z → Z, defined by (n) =-n for all n E Z B. ф: Z[x] Z, defined by ф(p(z)) p(0) for all p(z) E Z[2] C. : C C....
10 Let R be a commutative domain, and let I be a prime ideal of R. (i) Show that S defined as R I (the complement of I in R) is multiplicatively closed. (ii) By (i), we can construct the ring Ri = S-1R, as in the course. Let D = R/I. Show that the ideal of R1 generated by 1, that is, I R1, is maximal, and RI/I R is isomorphic to the field of fractions of D. (Hint:...
ring over Q in countably many variables. Let I be the ideal of R generated by all polynomials -Pi where p; is the ith prime. Let RnQ1,2, 3, n] be the polyno- mial ring over Q in n variables. Let In be the ideal of Rn generated by all ] be the polynomial rin 9. Let R = QlX1,22.Zg, 2 polynomials -pi, where pi is the ith prime, for i1,.,n. . Show that each Rn/In is a field, and that...
It is important.I am waiting your help. 11. a) Prove that every field is a principal ideal domain. b) Show that the ring R nontrivial ideal of R. fa +bf2a, b e Z) is not a field by exhibiting a 12. Let fbe a homomorphism from the ring R into the ring R' and suppose that R ker for else R' contains has a subring F which is a field. Establish that either F a subring isomorphic to F 13....
= Let R be a ring (not necessarily commutative) and let I be a two-sided ideal in R. Let 0 : R + R/I denote the natural projection homomorphism, and write ř = º(r) = r +I. (a) Show that the function Ø : Mn(R) + Mn(R/I) M = (mij) Ø(M)= M is a surjective ring homomorphism with ker ý = Mn(I). (b) Use Homework 11, Problem 2, to argue that M2(2Z) is a maximal ideal in M2(Z). (c) Show...
Q9 6. Define Euclidean domain. 7. Let FCK be fields. Let a € K be a root of an irreducible polynomial pa) EFE. Define the near 8. Let p() be an irreducible polynomial with coefficients in the field F. Describe how to construct a field K containing a root of p(x) and what that root is. 9. State the Fundamental Theorem of Algebra. 10. Let G be a group and HCG. State what is required in order that H be...
Example 1 provided for reference. Let K= {0, 1,RX+1} be the four-element field constructed in Example 1 on 206-207. Write X2+X+ 1 as a product of factors of degree 1 in K[X] Example 1 The polynomialx) X2+ X+1 is irreducible in Za[XI, since it has no roots in Z2. Thus (X)) is a maximal ideal in Z,[X), and Z[X]/(f(X is a field. Let us denote it by K. To see what K looks like, notice that the coset g(X) determined...