Anyone read this? How is it? I was never good at math and I have it on my "todo" list. Go back to some material from my high school and undergrad and fill the gaps. ;)
If you want to fill gaps, any typical undergrad calculus text will do such as Stewart's Early Transcendentals book. You do enough of those 8,000+ exercises and your highschool gaps will fill themselves. My favorite beginner math books are Thomas VanDrunen's Discrete Mathematics and Functional Programming because it's entirely done in SML, and Apostol's Calculus because you end up doing so many exercises you absolutely will never make a silly algebra mistake in a proof or forget a trig identity ever again. Often Apostol will just defer to endless calculating in the chapter exercises if he doesn't have anything he wants to add to the material, this is really good practice if your basic math education is shit like mine was.