Russell Lim – Medium

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Russell Lim
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The Greatest Mathematicians — A Data Visualisation

Our modern society is built upon mathematics. And mathematics is built upon the achievements of thousands of outstanding individuals…

5 min readJun 18, 2022

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The most influential mathematicians — a data visualisation.

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Russell Lim
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Nice Math Problems

A Very Nice Algebra Problem from the 2023 China Math Olympiad

The Chinese IMO team eat sequences like this for breakfast!*

10 min readJan 3, 2023

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A Very Nice Algebra Problem from the 2023 China Math Olympiad

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3

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Russell Lim
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Cantor’s Paradise

Least Squares vs Least Absolute Errors —A 250-Year-Old Debate

From Gauss and the birth of statistics to modern data science and machine learning

9 min readMay 8, 2022

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Scatterplot with least squares regression line and least absolute value regression line. Background image is brain and computer chip, symbolising artificial intelligence.

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Russell Lim
in
Nice Math Problems

Slicing a Cube With 8 Planes

is not so simple to visualize!

3 min read1 day ago

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Slicing a Cube With 8 Planes

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Russell Lim
in
Nice Math Problems

Can You Tell the Time on This Clock?

This clock is ambiguous — or is it?

8 min readApr 26, 2024

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Can You Tell the Time on This Clock?

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Russell Lim
in
Nice Math Problems

A Nice Factorial Equation from the 2024 Australian Mathematical Olympiad

Solve m! + k! = k! × n! for positive integers (k, m, n)

4 min readApr 11, 2024

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A Nice Factorial Equation from the 2024 Australian Mathematical Olympiad

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Russell Lim
in
Cantor’s Paradise

YES sin(𝜋/5) DOES Have an Exact Value

Calculating sin(𝜋/5) using Similar Triangles and the Pythagorean Theorem

3 min readApr 4, 2024

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sin(𝜋/5) is equal to half the side length of the regular pentagon inscribed in the unit circle

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Russell Lim
in
Nice Math Problems

Round Table Meetings and the Lemma that is NOT Burnside’s

A Fun and Practical Application of Group Theory

8 min readMar 26, 2024

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Round Table Meetings and the Lemma that is NOT Burnside’s

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Russell Lim
in
Cantor’s Paradise

The Golden Ratio — Hidden in Plain Sight! 🕵️‍♂️

(within a regular pentagon)

5 min readJan 25, 2024

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The Golden Ratio — Hidden in Plain Sight! 🕵️‍♂️

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3

Russell Lim
in
Nice Math Problems

Closed Curve on a Sphere

My favourite 💖 problem from the 2023 AMC 10

3 min readJan 8, 2024

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2

AMC 10B Question 20: 4 congruent semi-circles on a sphere

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Russell Lim

Russell Lim

Friend of Medium

I teach high school mathematics in Melbourne, Australia. I like thinking about interesting problems and learning new things.

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