A bit of maths

Complex numbers: an introduction

We will leave the domain of real numbers behind us and start exploring the plane of complex numbers. An introduction to a realm beyond imagination.

Lab centrifuges and prime numbers

Lab centrifuges are crucial in e.g. coronavirus research. It’s vital the test tubes are balanced. There is an easy method to know if that’s possible.

The Collatz Conjecture

The Collatz Conjecture is probably one of the easiest to understand problems which hasn’t yet been answered in the history of mathematics.
We see a monkey holding a mirror and looking in it, looking at itself.

Mirror, mirror, what’s up with the mirror writing?

Ever wondered why sentences, words, and letters always exclusively seem to have their left and right reversed in the mirror, while they are almost never projected upside down? Probably, because mirrors do something else than you would expect. For starters, mirrors don’t reverse left and right.
A photoshopped image of an out-of-focus dude with a beard holding a little sphere between his thumb and index finger in front of his face. The little sphere has a plus-sign on it. There are multiple spheres floating around with a minus-sign on them. Have a lovely day today!

Just a minute: Minus minus and negative times negative

Minus minus is plus. And negative times negative is positive. Two negatives make a positive. You may have heard or uttered these expressions many times. Even though you will know this already, here you will find an algebraic proof, just for your reference. Requirements: simple algebra from the second year…

The riddle of birthdays

Probabilities can be hard to grasp. For instance, what are the chances that among a birthday party’s attendants two or more people will have their birthdays on the same day? Probably better than you might expect.