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    so the step which says that \sqrt3 is a rational in lowest terms i think i understand it to mean that no matter what a and b are, provided there is a common factor you will always come back to "lowest terms" am i right of have i still dun goofed?
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    (Original post by will'o'wisp2)
    so the step which says that \sqrt3 is a rational in lowest terms i think i understand it to mean that no matter what a and b are, provided there is a common factor you will always come back to "lowest terms" am i right of have i still dun goofed?
    The way you say this makes me think that you have already been talking about it on another thread - if so, I haven't seen that, so I'm not sure exactly what you mean.

    But the idea is that you start off assuming that root 3 is a fraction in its lowest terms, so something like a/b where a and b have no common factors. You then do a series of steps that shows that a and b actually do have a common factor, contradicting your assumption, and therefore proving that root 3 can't be a fraction after all.

    Is this what you are asking, or is it something more specific?
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    (Original post by Pangol)
    The way you say this makes me think that you have already been talking about it on another thread - if so, I haven't seen that, so I'm not sure exactly what you mean.

    But the idea is that you start off assuming that root 3 is a fraction in its lowest terms, so something like a/b where a and b have no common factors. You then do a series of steps that shows that a and b actually do have a common factor, contradicting your assumption, and therefore proving that root 3 can't be a fraction after all.

    Is this what you are asking, or is it something more specific?
    This, cus i didn't understand what lowest terms meant and why it was important, but i understand the method to do a contradiction proof but i just can't do it lol.

    So what it's the same thing then? no common factors and lowest terms?
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    (Original post by will'o'wisp2)
    This, cus i didn't understand what lowest terms meant and why it was important, but i understand the method to do a contradiction proof but i just can't do it lol.

    So what it's the same thing then? no common factors and lowest terms?
    Yes. 4/10 is not in the lowest terms, but 2/5 is.
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    (Original post by will'o'wisp2)
    This, cus i didn't understand what lowest terms meant and why it was important, but i understand the method to do a contradiction proof but i just can't do it lol.

    So what it's the same thing then? no common factors and lowest terms?
    Any number that is rational can be written as a fraction in its lowest terms. E.g. 0.2 is rational and you can write it as 2/10 and 1/5 in its lowest terms.

    If you prove that it is impossible to write root 3 as a fraction in its lowest terms then it can't be rational.
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    (Original post by Pangol)
    Yes. 4/10 is not in the lowest terms, but 2/5 is.
    (Original post by Notnek)
    Any number that is rational can be written as a fraction in its lowest terms. E.g. 0.2 is rational and you can write it as 2/10 and 1/5 in its lowest terms.

    If you prove that it is impossible to write root 3 as a fraction in its lowest terms then it can't be rational.
    time to add this to my notes, thank you both
 
 
 
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