Factorise - For Your Eyes
MartinPacker 11000094DH Visits (2026)
If there’s one thing I would be doing if I weren’t doing this it might be teaching maths - but it would have to be at a level where algebra and calculus were substantial topics. But I don’t think I’ll really be doing that - at least not for the foreseeable future. 
So it occurred to me that I need not be alone in treating some algebraic techniques as puzzles - and with automatic generation of problems people could really get quite good at it. That might be useful - though utility is not my prime motivator in liking algebra: I almost never get to use it.
After a brief preamble about factorisation and some hints it presents you with a machine-generated second-order polynomial in x to factorise. You type in the factors and press the “Check” button.
The code multiplies the factors together and tells you what the resulting polynomial is. It also compares it to the original and tells you if you’ve got it right.
There’s a “Try another” button or you can just manually reload the page.
Try the code here.
It’s a little rough and ready. In particular you have to be little careful in how you type the factors in.
I’ve thought of some ways I could improve it already:
But for now I’m enjoying testing it. And I hope you enjoy playing with it too.
And, in case you’re wondering, I have a memory-related “day job” post beginning to take shape in my brain.