Maths, finally

So, this week I finally got back to the Maths – I did a deal with myself that if I at least started on finishing off the Year 11 stuff, I could also start on the Year 12 book. So I have now sent in the final two tutorials for Year 11, and done revision notes for one of the four chapters I still have to do – then there is an assessable assignment and an exam to finish it all off.

The revision notes I have done were on the chapter introducing limits and differentiation. An interesting thing is mentioned which also struck me when I first read it – did you know that the rate of change of the area of a circle with respect to its radius is the circle’s circumference (A = πr² and dA/dr = 2πr) – and also that the rate of change of the volume of a sphere with respect to its radius is the sphere’s surface area (V = 4/3πr³ and dV/dr = 4πr²). I have no idea whether that has any real significance but it struck me as interesting (and a really good way of remembering the formula for the surface area of a sphere).

And, after all my hopes that at least now I’m working out of an official textbook, I wouldn’t have to contend with all the bugs, the answer given in the back of the book for the third part of the very first question in chapter one is - you guessed it - WRONG. Luckily the question is so simple that it’s very obviously a wrong answer, but it’s still a bit annoying. Once again, I ponder a career as a proofreader ….