Proving the Identity: gcd(a, lcm(b,c))

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SUMMARY

The identity gcd(a, lcm(b,c)) = lcm(gcd(a,b), gcd(a,c)) is confirmed as true based on the properties of prime factorization. The proof relies on the relationship between the exponents of the prime factors in the canonical forms of a, b, and c. Specifically, the equality min(a,max(b,c)) = max(min(a,b),min(a,c)) holds, demonstrating the validity of the identity.

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  • Understanding of greatest common divisor (gcd) and least common multiple (lcm)
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Is this identity true?

gcd(a, lcm(b,c)) = lcm(gcd(a,b), gcd(a,c))
 
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What have you tried so far?

Have you looked for counter examples or attempted a proof?

Do you have an idea of how to prove/disprove statements like these?
 
I have already proven it, since the exponents of the all primes of the canonical factorization of a, b and c obeys min(a,max(b,c))=max(min(a,b),min(a,c)).
 

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