(no subject)
Jan. 10th, 2002 12:00 amI just discovered that the math department has a `problem of the month' contest here, so I just solved the January problem. Hopefully I'll win a neat book or something.
The problem is this: ``Given rational numbers x, y, z such that 1/x + 1/y + 1/z, show that the distance from the point (x,y,z) to the origin (0,0,0) is rational.'' It's very simple to prove algebraicly. Just let x=a/b, y=c/d, z=e/f for integers a, b, c, d, e, f. Then f/e = - (b/a + d/c) = - ((bc + da)/ac). Plug this into sqrt((a/b)^2 + (c/d)^2 + (e/f)^2) and it comes out quickly. I imagine there must be a `cooler' way that they're looking for.
I have teeth coming in (way in the back) and they *hurt*. Been taking Aspirin at maximum recommended dosage.
Played with a copy machine for a little while and made myself some Estonia-themed letter writing stationary.
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