Can You Find an Irrational Number Between Two Rational Fractions?

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To find an irrational number between two rational fractions a/b and c/d, one can use the difference formula (ad-bc)/(bd) to determine the gap between them. By selecting a strictly increasing curve, such as y=x^2 for x>0, one can identify x values that correspond to the given fractions and then find a y value that lies between them. This method guarantees that the resulting number will be irrational. The discussion emphasizes the importance of ensuring the chosen irrational number is smaller than the calculated difference. The approach suggested by Carl is confirmed to be effective for this purpose.
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ok,

a/b c/d

a,b,c,d are all integers
b and d are > 0

find a number inbetween a/b and b/d using a,b,c,d that is an irrational number.

thanks :!)
 
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The difference between the two rational numbers is

\frac{ad-bc}{bd}

If you can find an irrational number that is smaller than this, you can add it to the lesser of {a/d, b/c}.

Carl
 
You could pick a strictly increasing curve (like y=x^2, for x>0), find the x values that generate these two fractions as y values, and find the y value for the number halfway (or anywhere) between these two x values. It's a safe bet this will be an irrational number.
 
CarlB said:
The difference between the two rational numbers is

\frac{ad-bc}{bd}

If you can find an irrational number that is smaller than this, you can add it to the lesser of {a/d, b/c}.

Carl
so that will work for sure carl?
 
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