First, my solution to Old Exam Question #4
(Click for enlargements)
You may notice I couldn’t see the wood for the trees in my original solution. I got an idea stuck in my head and ran with it, which is fine (and was fun!), but there was a much, much quicker way to do it (there usually is with maths). Shortcut is below.
And now onto the latest question. This is from an Additional Maths 1971 O Level paper: