Today our 6-year-old kept asking for my phone. I was watching a basketball game, or trying to, so around the fourth time I gave it to her. Phone for peace. When there was a timeout, I checked in on her, and discovered that she had the calculator app open. She'd punch in, like, 6 + 4, and then there'd be a pause before she touched the equal key and I could hear her say softly to herself either "Yes!" or "Ach!" What a little dweeb.

I suppose she comes by it honestly. About once a week I ask the teenager what the current topic is in math class. That's always good for the eye roll, and, on rare occasions, an answer, such as, recently, "Circles." Oh, boy, I am really interested in circles! Give me an example of a problem! For the first time in recorded history, she obliged, and soon we were figuring out the area inside a sixty degree sector of a circle of radius 1 but outside the triangle made by the radii and the chord. That makes it sound harder than it is--it's just the shaded area in the figure, only with the radius of 6 changed to 1. She's in 8th grade. Maybe I like this stuff partly because I wish I was in 8th grade myself. Beats hell out of being 58. Anyway, for the dweebs, the area of the whole circle would be π. So the area of the sixty degree sector would be a sixth of that, π/6. The triangle made by the radii and the chord would in this case be equilateral, one unit on all sides, and the area of that would be . . . . well, suppose you don't want to google the formula for area of an equilateral triangle. The area of any triangle is the product of half the base and the height. Half the base would be 0.5. The height may be thought of as one leg of a right triangle where the other leg is 0.5 and the hypotenuse is 1. By the Pythagorean Theorem, that works out to be √3/2. So the area of the whole triangle would be half of that, √3/4. And the area we want is the difference between that and π/6, that is, (π/6 - √3/4).

I lecture Rianna in the manner of my dad. "If this answer is correct, it had better be quite a small positive number, right?" A calculator puts it at just a touch under 0.09, which seems plausible.

Maybe the ACC is not that great? If Duke wins, it will have two entrants in the Sweet Sixteen, and the Big Ten has three. Plus, it took a couple of #1 seeds to eliminate Michigan State and Northwestern (sic).

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