Let Z[ √ 2] = {a + b √ 2 | a, b ∈ Z}. (a)...

Let Z[ √ 2] = {a + b √ 2 | a, b ∈ Z}. (a) Prove that Z[ √ 2] is a subring of R. (b) Find a unit in Z[ √ 2] that is different than 1 or −1.

Expert Solution

Colby Messinger answered 2 years ago

Suppose A = {(a, b)| a, b ∈ Z} = Z × Z. Let R be...

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