Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Poor book for students

This book does an OK job up to about the 5th chapter. After that point, the exercises at the end of each chapter get considerably more difficult. Up until that point, the assignable problems and the sample problems in each chapter are very similar in terms of difficulty. Once chapter 5 begins, the sample problems in the text are completely useless as for deriving the differential equations necessary to solve the assignable problems. The only sample problems given in chapter 5 and beyond are real simple "plug and chug" type examples compared to the difficult problems at the end of the chapters. It's like showing someone how 2x4s can be nailed together and then asking someone to build a skyscraper. No fun.