An accurate 12-hour analog clock has an hour hand
Source: IMO Longlist 1989, Problem 101
September 18, 2008
algebra unsolvedalgebra
Problem Statement
An accurate 12-hour analog clock has an hour hand, a minute hand, and a second hand that are aligned at 12:00 o’clock and make one revolution in 12 hours, 1 hour, and 1 minute, respectively. It is well known, and not difficult to prove, that there is no time when the three hands are equally spaced around the clock, with each separating angle Let be the respective absolute deviations of the separating angles from \frac{2 \cdot \pi}{3} at hours after 12:00 o’clock. What is the minimum value of