Let D and D'be integral domains. Let c = charD and c'= charD' (a) Prove that...

Let D and D'be integral domains.

Let c = charD and c'= charD'

(a) Prove that the direct product D ×D'has unity.

(b) Let a ∈D and b∈D'.

Prove that (a, b) is a unit in D ×D'⇐⇒

a is a unit in D, b is a unit in D'.

(d) Prove that if c, c'> 0,

then char(D ×D') = lcm(c, c')

(e) Prove that if c = 0, then char(D ×D') = 0.

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Expert Solution

Colby Messinger answered 1 year ago

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