Reduced Noetherian implies zero divisor in minimal prime

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Statement

Suppose A is a reduced Noetherian ring: in other words, it has no nilpotents, and every ideal is finitely generated. Then, any zero divisor in A must be inside some minimal prime ideal of A.

(For non-Noetherianness, we can only say that every zero divisor must be inside some prime ideal, since minimal primes are not guaranteed to exist).

Proof

Suppose aA is a zero divisor. Then, there exists 0bA such that ab=0. Clearly, we have that ab is in every minimal prime. If a is not in any minimal prime, then b must be in every minimal prime, hence b must be in the intersection of all minimal primes. But the intersection of all minimal primes is the intersection of all primes, which is the nilradical. Since we're in a reduced ring, this is zero, so b=0, a contradiction.