Author: Colin

Ask Uncle Colin: A factorising trick

Dear Uncle Colin, How would you factorise $63x^2 + 32x – 63$? I tried the method where you multiply $a$ and $c$ (it gives you -3969) – but I’m not sure how to find factors of that that sum to 32! Factors Are Troublesomely Oversized, Urgh Hi, FATOU, and thanks

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Wrong, But Useful: Episode 62

In this month’s episode of Wrong, But Useful, we’re joined by @ch_nira, who is Dr Nira Chamberlain in real life – and the World’s Most Interesting Mathematician. Nira is a professional mathematical modeller, president-designate of the IMA, and a visiting fellow at Loughborough university. We discuss Nira’s entry in the

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Bone Marrow Odds

I don’t remember doing it – although I’d meant to for some time – but apparently I signed up for the British Bone Marrow Registry. (If you’re between 17 and 40, you can sign up the next time you give blood; the more people on the register, the more likely

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Ask Uncle Colin: A Mess of Logs

Dear Uncle Colin, I have to show that \(-\frac{x}{2} = \ln (\sqrt{1+e^x} – \sqrt{e^x }) + \ln (\sqrt{1+e^{-x}} + 1)\). I can’t get it anywhere near the right form! – Proof Of It Not Coming – Any Reasonable Explanation? Hi, POINCARE, and thanks for your message! That’s a bit of

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Exchange rates on board

“Three teas, please,” said the passenger ahead of me in the queue. The Armorique was due in Plymouth any minute, and tea was of the essence. “That’s £4.65, or €5.601.” Hang on a moment, I thought, remembering to order my own tea as well. 560 isn’t a multiple of 3.

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Maths, Magnus Carlsen, and Making Decisions

An emergency blog post about chess, of which I know nothing. This is not meant as serious analysis; think of it more as “here are some topical maths ideas you can throw at your classes.” So, I looked up the Elo ratings for the chess world championship players: in rapid

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Ask Uncle Colin: A Cubic That Won’t Come Good

Dear Uncle Colin, I’m told that \(x\sqrt{x} – 5\sqrt{x} = 2\) and I have to find \(x – 2\sqrt{x}\). Everything I try seems to make it worse! Any ideas? Mastering A Cubic – Help Is Needed Hi, MACHIN, and thanks for your message! At first glance, that’s a strange one.

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All The Maths Podcasts

Since @reflectivemaths wasn’t at Big MathsJam and @samuelhansen was, the MathsJam Special is a bit different this year.

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The Mathematical Ninja and the Variable Volume

The student, at the third time of asking, navigated the perilous straits of negative powers and fractions of $\pi$ and came to rest, exhausted, on the answer: “$r^3 = \frac{500}{\pi}$,” he said. The Mathematical Ninja stopped poking him with the foam sword (going soft? perhaps. Or perhaps this student needed

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Ask Uncle Colin: How do I keep my head up?

Dear Uncle Colin, As I progress through my maths education, I notice that the people around me are getting smarter and smarter. How do I keep my head up when everyone is brighter than me? I’m Mightily Put Off Seeing Their Outstanding Results Hi, IMPOSTOR, and thanks for your message!

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Where do you teach?

I teach in my home in Abbotsbury Road, Weymouth.

It's a 15-minute walk from Weymouth station, and it's on bus routes 3, 8 and X53. On-road parking is available nearby.

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