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Exercise 263Number theory › PrimesHigh schoolAdded 3 Nov 2026

Distinct primes are coprime

#coprime#primes#distinct

Statement

Show that distinct primes p,qp,q are coprime.

Hint

The only divisors of pp are 11 and pp.

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Solution

Divisors. gcd⁡(p,q)\gcd(p,q) divides pp, so it is 11 or pp.

If pp. Then p∣qp\mid q, but qq is prime with q≠pq\neq p, contradiction (as p>1p>1).

Conclusion. gcd⁡(p,q)=1\gcd(p,q)=1.