Going through some of my notes I rediscovered this mnemonic for the quadratic formula:
From square of b, take 4ac;
Square root extract, and b subtract;
Divide by 2a; you’ve x, hooray!
I am not sure of the origins of this mnemonic. The earliest version I could find was from J. S. Mackay in 1894, but he says the mnemonic was given to him by a member of the Edinburgh Mathematical Society.
Here’s another mnemonic for the quadratic formula:
And let’s not forget the Quadratic Formula Rap:
The books of philosopher, mathematician, magician, musician, Raymond Smullyan are priceless. If you are not familiar with his work, his autobiography is good place to start.
I own many books by Smullyan. Including these:
I have also been working through his book Set Theory and the Continuum Problem
The amazing Arthur Benjamin makes the argument that statistics, not calculus, should be the goal of mathematics education.