Let f : R → S and g : S → T be ring homomorphisms. (a)...

Let f : R → S and g : S → T be ring homomorphisms.

(a) Prove that g ◦ f : R → T is also a ring homomorphism.

(b) If f and g are isomorphisms, prove that g ◦ f is also an isomorphism.

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Expert Solution

Colby Messinger answered 4 months ago

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