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Prove or disprove: if p and q are prime numbers then pq - 2 is also a prime number.
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Prove or disprove: if p and q are prime numbers then pq - 2 is also a prime number.

User Andreq Frenkel
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1 Answer

7 votes

Counterexample:


image

4 is not a prime number. So, it's false.

User Sdhaus
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