Core 3 basics revision quiz Apr 2, 2013 [mtouchquiz 4] A selection of other posts Jul 15, 2020 Ask Uncle Colin: Why does the $ac$ method work? May 10, 2017 Ask Uncle Colin: an arctangent mystery Jan 27, 2016 Ask Uncle Colin: A Limiting Issue Oct 24, 2013 Wrong, But Useful: Episode 8 subscribe via RSS