Euclid contributed to number theory, which is the study of integers. He worked on prime numbers and divisibility. He proved the infinitude of prime numbers, which had not been proven before.
No one invented prime numbers.
Euclid
Euclid proved that it is impossible to find the "largest prime number," because if you take the largest known prime number, add 1 to the product of all the primes up to and including it, you will get another prime number. Euclid's proof for this theorem is generally accepted as one of the "classic" proofs because of its conciseness and clarity. Millions of prime numbers are known to exist, and more are being added by mathematicians and computer scientists. Mathematicians since Euclid have attempted without success to find a pattern to the sequence of prime numbers.
You can use Euclid's algorithm to calculate the gcf of two of the numbers - then use Euclid's algorithm again with the result and the third number.Or you can factor all the numbers into prime factors, and check which prime factors occur in all three numbers.
Euclid contributed to number theory, which is the study of integers. He worked on prime numbers and divisibility. He proved the infinitude of prime numbers, which had not been proven before.
invention of natural numbers
No one invented prime numbers.
Euclid
The Egyptians were the first people to have some knowledge in prime numbers. Though, the earliest known record are Euclid's Elements, which contain the important theorem of prime numbers. The Ancient Greeks, including Euclid, were the first people to find prime numbers. Euclid constructed the Mersenne prime to work out the infinite number of primes.
Euclid proved that it is impossible to find the "largest prime number," because if you take the largest known prime number, add 1 to the product of all the primes up to and including it, you will get another prime number. Euclid's proof for this theorem is generally accepted as one of the "classic" proofs because of its conciseness and clarity. Millions of prime numbers are known to exist, and more are being added by mathematicians and computer scientists. Mathematicians since Euclid have attempted without success to find a pattern to the sequence of prime numbers.
Euclid
Euclid
No, prime numbers already existed. Euclid simply made some important mathematical contributions related to prime numbers. Among others, he discovered a surprisingly simple proof that the set of prime numbers is infinite; and he discovered that the prime factorization of any natural number is unique.
Was demonstrated by Euclid around 300 B.C
You can use Euclid's algorithm to calculate the gcf of two of the numbers - then use Euclid's algorithm again with the result and the third number.Or you can factor all the numbers into prime factors, and check which prime factors occur in all three numbers.
Euclid's algorithm is probably the most commonly used 'formula' for that purpose. If the greatest common factor is 1, the numbers are relatively prime. See the related question for an example of Euclid's algorithm.