Relatively Prime Numbers (Coprimes, Mutual Primes) | Pre-Algebra

CORRECTION: I said the only factors of 15 are 1, 3, and 5. I forgot to include 15, which is indeed a factor of 15. Thanks to Alex Faus in the comments for pointing this mistake out.

Prime numbers are extremely cool, and it turns out they have a slightly less cool cousin called relative primes, relatively prime numbers, mutual primes, mutually prime numbers, coprimes, or coprime numbers. What are relatively prime numbers? We go over that in this math lesson. Relatively prime numbers, mutual primes, or coprimes, are number which have no common factor greater than 1. For example, the factors of 6 are 1, 2, 3, and 6. The factors of 7 are 1 and 7, so the only common factor 6 and 7 have is 1. Therefore, they are relatively prime. 4 and 6 are not relatively prime because their largest common factor is 2. 1 and -1 are the only numbers relatively prime to every number, because they are the only numbers (we are only considering integers) whose largest factor is 1. Additionally, 1 and -1 are the only numbers relatively prime to 0.

I hope you find this video helpful, and be sure to ask any questions down in the comments!

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[expansivegymnast]

Good video. I'm studying discrete math and I needed a refresher on this stuff.

[FRODOGOOFBALL]

When I was in school they taught us "lowest common denominator" and "greatest common denominator", but never mentioned the phrases "relatively prime" or "least common multiple". So thanks for clarifying this!

[gwinettealmendras]

Thanks it helped! Now i know if the numbers relatively prime! TYSM for this video mr. Wrath. I hope you had a good day.😊

[ThantSinAung-udyx]

This channel is gold! subscriber count is too low for such a treasure.

[NicoleFry]

Thanks i dont understand untill i see your video thankssss

[mandarbendre]

This helped soo much for my math homework, now I know what relatively prime is

[angelicadelfinbarrio]

THANK YOU SO MUCH SIR! THIS HELPED ME A LOT

[junnururamachandrarao]

Thank you sir you made me the concept crystal clear.

[alexfaus]

Nice video but one of the factors of 15 is 15 which you left out unfortunately

[manal]

Sorry but in " they've no common factor other than one " does that mean that only 1 ( the integer one ) is allowed or other numbers are allowed ( like 4, 6 ... ) but we only take one of them ?

[juliagomez]

How do you determine if variables are relatively prime? I saw you kind of included this in the video, but I don't get it. Also do variables with exponents have a method to know if they are relatively prime with another term? If so, can you explain?

[anjanikeshari]

Sir I have one question and I don't know how to solve the question is If a and b are relatively coprime, prove that LCM of ma and mb is mab. Sir please tell me the solution of this problem.

[kirtikajla]

Is there any difference between relatively prime and co prime number

[avinashsrivastav]

Is there any difference between relatively coprime and and co prime no

[omgvn]

Did someone get bored one day and make up this concept? I wonder when will this ever be needed. And GCD, GCF, HCF and HCF are all the same thing. It’s like they throw acronyms everywhere so my brain can take a walk 🤣

[MSubscribersMViews]

Find the number of divisors of 3 and 5 in between 500 and 1000. Sir plz help me.