Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Probably one of the worst math textbooks period

I am an undergraduate student taking PDEs now and this is our textbook. Please don't listen to others who gave this a good review. This book has no concrete organization. The exercises are horrible. And they assume so much. Instead of convincing us that a mathematical step is valid, they ask us to trust them, because the proof is too advanced. The problem with this teaching style is that there is nothing, no logical understanding, to grasp onto, which is what students need to retain something in their brain! Please if you are a professor using this book, just take a little time during class to ask your students what they think. I guarantee you wont be using this book again.