Maths is a cumulative subject. I am picking it up again and falter (as I have before) around trigonometry (esp. trig. - God do I hate trig.), functions, and calculus. My route to learning these is usually scattered and inconsistent. Can anyone describe a linear learning route through these fundamentals to make the process any more straight forward? Seems like a mess of contingencies to me, but my IQ is probably very low.