Proof with rationals and irrationals

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SUMMARY

The discussion centers on proving that any rational number in the interval (0,1] can be expressed as a finite sum of the form r = 1/q1 + 1/q2 + ... + 1/qn, where qj are integers and q1 < q2 < ... < qn. The suggested approach involves utilizing the greedy algorithm to construct the integers q1, q2, ..., qn. Participants recommend starting with specific rational examples to simplify the proof process before generalizing to all rationals.

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Homework Statement


Show that any rational in the interval (0,1] can be expressed as a finite sum r=1/q1+1/q2+...+1/qn where the qj are integers and q1<q2<...<qn.


Homework Equations





The Attempt at a Solution


Let x\inQ and 0<x\leq1.
Prove \existsq1, q2, ..., qn\inN with q1<q2<...<qn.

My professor suggests using the greedy algorithm but I don't understand how that would help the proof.
 
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Since you're having trouble tackling the problem for all rationals, have you tried first working on the simpler problem of just considering some rationals? Maybe certain classes of them, or just pick seven at random and see what you can do?
 

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