Question

Let F and L be fields, and let φ : F → L be a ring...

Let F and L be fields, and
let φ : F → L be a ring homomorphism.

(a) Prove that either φ is one to one or φ is the trivial homomorphism.

(b) Prove that if charF= charL, then φ is the trivial homomorphism

Homework Answers

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Let B = { f: ℝ  → ℝ | f is continuous } be the ring of...
Let B = { f: ℝ  → ℝ | f is continuous } be the ring of all continuous functions from the real numbers to the real numbers. Let a be any real number and define the following function: Φa:B→R f(x)↦f(a) It is called the evaluation homomorphism. (a) Prove that the evaluation homomorphism is a ring homomorphism (b) Describe the image of the evaluation homomorphism. (c) Describe the kernel of the evaluation homomorphism. (d) What does the First Isomorphism Theorem for...
Let φ : A → B be a group homomorphism. Prove that ker φ is a...
Let φ : A → B be a group homomorphism. Prove that ker φ is a normal subgroup of A.
Let E/F be an algebraic extension. Let K and L be intermediate fields (i.e. F ⊆...
Let E/F be an algebraic extension. Let K and L be intermediate fields (i.e. F ⊆ K ⊆ E and F ⊆ L ⊆ E). (i) Prove that if the extension K/F is separable then the extension KL/L is separable. (ii) Prove that if the extension K/F is normal then the extension KL/L is normal. Note: To make things easier for you, you can assume that E/F is finite (hence all extensions are finite),
Let φ:G ——H be a group homomorphism and K=ker(φ). Assume that xK=yK. Prove that φ(x)=φ(y)
Let φ:G ——H be a group homomorphism and K=ker(φ). Assume that xK=yK. Prove that φ(x)=φ(y)
Let G be an Abelian group. Let k ∈ Z be nonzero. Define φ : G...
Let G be an Abelian group. Let k ∈ Z be nonzero. Define φ : G → G by φ(x) = x^ k . (a) Prove that φ is a group homomorphism. (b) Assume that G is finite and |G| is relatively prime to k. Prove that Ker φ = {e}.
Let φ : G → G′ be an onto homomorphism and let N be a normal...
Let φ : G → G′ be an onto homomorphism and let N be a normal subgroup of G. Prove that φ(N) is a normal subgroup of G′.
Prove the following theorem: Let φ: G→G′ be a group homomorphism, and let H=ker(φ). Let a∈G.Then...
Prove the following theorem: Let φ: G→G′ be a group homomorphism, and let H=ker(φ). Let a∈G.Then the set (φ)^{-1}[{φ(a)}] ={x∈G|φ(x)} =φ(a) is the left coset aH of H, and is also the right coset Ha of H. Consequently, the two partitions of G into left cosets and into right cosets of H are the same
Let R be a ring. Show that the set Aut(R) = {φ : R → R|φ...
Let R be a ring. Show that the set Aut(R) = {φ : R → R|φ is a ring isomorphism} is a group with composition.
Let M = { f: ℝ  → ℝ | f is continuous } be the ring of...
Let M = { f: ℝ  → ℝ | f is continuous } be the ring of all continuous functions from the real numbers to the real numbers. Let a be any real number and define the following function: Φa:M→R f(x)↦f(a) This is called the evaluation homomorphism. 1. Describe the kernel of the evaluation homomorphism. 2. Is the kernel of the evaluation homomorphism a prime ideal or a maximal ideal or both or neither?
Consider the map φ :Mnxn (R) → R defined by φ(M) = det(M), where det(M) is...
Consider the map φ :Mnxn (R) → R defined by φ(M) = det(M), where det(M) is the determinant of the matrix M. Is φ a ring homomorphism? Prove or disprove.