If you find a legitimate PDF through AoPS or your school library, it’s an outstanding resource. Just pair it with a problem-solving companion (e.g., Calculus: Early Transcendentals problems) for exam prep.
Here’s a solid, balanced review for Calculus by David Patrick (often encountered as part of the AoPS curriculum, though note that David Patrick is better known for other AoPS titles; if you mean his Calculus: The Art of Problem Solving approach, this review fits). A rigorous, proof-light calculus text for problem solvers – great for self-study, but not for everyone calculus by david patrick pdf
If you’re looking for a standard college calculus textbook (like Stewart or Thomas), Calculus by David Patrick is not that. Instead, this book (often available as a PDF through AoPS or institutional access) takes a aimed at motivated high school students, competition math enthusiasts, and independent learners. If you find a legitimate PDF through AoPS