Calculus Made Easy (1914) [pdf]
I'm embarassed somewhat to say this, but over the past few weeks I've been taking the courses on Khan Academy on mathematics. I'm nearly 30.and I'm not talking about brushing up on my linear algebra, that comes later, I'm talking high school level mathematics, stuff that I've largely forgotten or didn't "get" first time round.I've seen these "machine learning for hackers!" articles who try to dish out a bit of maths saying that's all you need, but I don't think you can escape the fact that sometimes you just need to start from the beginning and work your way up