Is It possible to fail my math course without a math book? I can’t afford my professors math book but I’m doing all his homework and getting decent grades in my exams but I heard that a professor can fail you if you don’t have his required book.
Your grade is based on the criteria set forth in the syllabus the professor handed out at the beginning of the course.
How would this person even know that you don’t have the book?
There should be a copy in your university library. Go there an check it out.
Is there a code you need to buy to complete assignments on line or take tests?
I wonder if you could request that the college library buy a copy of the book. Maybe they already have one. Another option could be to rent a copy from Amazon or elsewhere online.
A professor can penalize you if you do not do required assignments that happen to be in the book. You’re fine.
Ideas if you can’t afford a book:
- Do you know any upper classmen with the book?
- Ask a classmate if you can take pictures of the chapter with your phone
- Talk to the professor…they may have a copy you could borrow
- There may be a copy of the book in the library on reserve (you can look at book in library but can’t check it out)
- Look on ebay or amazon or chegg for cheaper copies of the book
- Rent, or better yet Rent a used copy of the book (through amazon or your bookstore)
I’m not sure I’d talk to the prof. They make money if you buy the book. I’ve known profs who would not be happy.
Don’t believe everything you hear. 
While other users have given valid options to get your hands on the book, to answer the question, assuming that owning the book was not listed in the grading rubric, no, the professor will not fail you.
Ask for help. If you have real financial issues, sometimes the Dean of Students have access or know of book scholarships/funds on campus. It is easier to do well when you have all the tools.
In any case, don’t fail because you don’t have a book and can’t do the reading. Start off with your professor.