Comments by "Mikko Rantalainen" (@MikkoRantalainen) on "Math Queen" channel.

  1. I would have solved this by noting that the circle is on diagonal and therefore r + (horizontal part of radius r along the diagonal of the big square) must sum to 2. Since sin(45 degrees) = 1/sqrt(2) you get the same result.
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  2. Comparing 42^99 and 99! would have been much harder.
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