Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Worst Textbook Ever

This textbook is too concise (it is 469 pages; for comparison, Linear Algebra, by David Poole is 763 pages) and the examples are not instructional at all. The problems are difficult and you will not know how to do the problems even after you have read the text because of its poor explanation of concepts. The publisher's website contains a solution manual to the problems, but even it doesn't explain things clearly. Unless your teacher is excellent, you will have a difficult time if you take a course that uses this book. You will most likely have to read other texts or use the internet to actually learn. This book is definitely not recommended for self-study. I would say that it is not even worth $10 considering that there are plenty of free (legal) linear algebra textbooks on the web.