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the root 3 irrational proof stuff again watch

1. so the step which says that 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?
2. (Original post by will'o'wisp2)
so the step which says that 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?
3. (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?
4. (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.
5. (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.
6. (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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