WitCH 81: Pointed Criticism

This is another one courtesy of Mysterious Michael. We’re not quite sure whether it’s a WitCH, or a PoSWW, or one for the error list, or simply a roll-your-eyes-and-ignore. In any case, it’s a question from the notorious 2016 Methods Exam 2 (report here), and we’ve expanded slightly from MM’s stated concern. (We could’ve expanded to include the entire question, as a Road to Nowhere, but decided not to lose too much of MM’s original focus.)

Have fun.

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WitCH 80: External Forcing

Yep, it’s Golden Ratio Day here at Mathematical CrapLand.

This is a weird one. It might be trivial, or very hard, or non-existent. We’re not 100% sure. (OK, we are sure, but it took a while.) Anyway, it’s a research paper appearing in a (not the)┬ájournal published by Nature, and so can tolerate a little extra scrutiny. The paper, titled The golden number seen in a mechanical oscillator, appeared a couple weeks ago in the open access Nature journal, Scientific Reports; the paper can be downloaded here. Here is the begining: Continue reading “WitCH 80: External Forcing”

WitCH 79: Cos Why Not?

Yeah, we’re busy, but this one has been bugging us. It is an exercise and solution from Cambridge Specialist Mathematics 3&4. It’s basically a PoSWW, or we could simply let it pass as a textbook glitch. But we think there’s more than the obvious to say.

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WitCH 78: Seeing Through De Carvalho’s Prism

Happy April Fools’ Day everyone. Guess which gang of fools is gonna get fooled, and guess which gang of fools is gonna do the fooling.

There’s not a whole lot of point to this any more, but it’s niggling. So we’ll post again on ACARA‘s thoughtful and classy CEO, David┬áde Carvalho.
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WitCH 77: Road to Nowhere

If nothing else, people can enjoy a great song.

This one puzzled us when we gave the 2021 Further Mathematics Exams a three-minute scan, but we didn’t bother then to think, um, further. Now, however, since graph theory is likely a mandatory part of Specialist 1&2, and thus also, at least technically, a mandatory part of Specialist 3&4, we have thought a little harder. So, after discussions with John Friend and with a colleague who we shall refer to as Professor Combo, here we are.

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WitCH 72: High Significance

Here is one more from the 2019 Specialist Exam 2, once again courtesy of student PURJ (who is vetting the exams much better than the exam vetters). It consists of the last four parts of Q6, the final question on the exam, concerning a machine that packages noodles. The answers from the examination report appear below the questions.

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