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Posts Tagged "everyday math"

Roots of Unity

Mathematicians Predict What’s in Your Wallet

It's all about the Washingtons. And that smiley face button. Image: flickr user xJason.Rogersx

When I go to Europe, my pockets rapidly fill up with change. In addition to language barriers that prevent me from quickly understanding how much I owe, I have trouble dealing with the unfamiliar coin denominations. The best way to make 75 cents is to use a fifty cent piece, one twenty, and a five, [...]

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Roots of Unity

My Head Is Not a Hairy Ball

hairy ball

I’ve been thinking about the hairy ball theorem a lot recently. Because I have the sophisticated sense of humor of a twelve-year-old just got a haircut, and I am newly reminded of my cowlicks. At this length, I’m much more aware of my hairs as vectors than I was when they were longer. A vector is [...]

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