Here is a secret that frustrated searchers often miss: You don't always need the whole PDF. Because the book is so popular, the ancillary materials are often legally available via Google links.
: A direct PDF version of the 2nd Edition hosted on Google Drive. patrick m fitzpatrick advanced calculus pdf google link
While not strictly "free" in the pirate sense, the Internet Archive’s frequently has a digitized copy of Fitzpatrick’s text. You can "borrow" the PDF for 1 hour or 14 days via controlled digital lending. This is legal, safe, and requires only a free account. Here is a secret that frustrated searchers often
Leo sat in silence. He looked at his problem set. Problem 4 was the only one he had left. He solved it in twenty minutes using the corrected theorem from page 312. While not strictly "free" in the pirate sense,
When searching for a "google link" for this PDF, you are likely looking for the , published by the American Mathematical Society (AMS) as part of their "Pure and Applied Undergraduate Texts" series. 1. University Repositories (The "Google Link" Method)