Let A be a commutative ring and F a field. Show that A is an algebra...

Let A be a commutative ring and F a field. Show that A is an algebra over F if and only if A contains (an isomorphic copy of) F as a subring.

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Colby Messinger answered 1 year ago

Let F be a field and let φ : F → F be a ring isomorphism....

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