Someone on this forum mentioned to me the book calculus for dummies is a book, and even though the author mentions what he says isn't strict by any means, people have told me its a waste of money. Is this true? At least, it makes the concepts easier to grasp. For an example the integral (the anti derivitave ) he explains that the interval with a limit (without the +C) from a to b is like taking a object and its curvature and the a is the bottom and the b is the top. is this a good way to look of it?