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Thread: Prove that √15 is irrational.

  1. February 23rd 2010, 09:27 AM #1
    feyomi
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    Prove that √15 is irrational.

    Question: Prove that √15 is irrational.

    Answer:
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  2. February 23rd 2010, 10:05 AM #2
    tonio
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    Quote Originally Posted by feyomi View Post
    Question: Prove that √15 is irrational.

    Answer:

    Hint: mimick Euclides proof for \sqrt{2} choosing an appropiate prime.

    Tonio
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« gcd(a,b,c)lcm(a,b,c) = abc =>gcd(a,b)=gcd(b,c)=gcd(a,c)=1 | Show that is gcd(a,b)=1, and both a and b divide c, then ab divides c. »

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