Thanks for your question, which I will respond to in a second. First let me explain how we got to 550 pages. I wanted to include a review of prerequisites mater

Thanks for your question, which I will respond to in a second. First let me explain how we got to 550 pages. I wanted to include a review of prerequisites material from high school math, which burned 100pp right off the batt. Then the main material (Ch2-Ch6) is just 220pp which is not bad (especially when you take into account the book is a compact format 5.5" x 8.5"). All of this was done in 2014, when I started to think about the applications of linear algebra. But then the feature creep starts! In the introduction of the book I make the claim about how powerful LA techniques are, and how they serve as the foundation of machine learning, and generally "scientific modelling." To substantiate this claim, I decided to make a kick-ass applications chapter that SHOWS how powerful linear algebra really is (show me, don't tell me). Two years later, the result is a 270-page survey of pretty much everything I've learned over the years from engineering, physics, and computer science that used linear algebra. > why this book? what does it really do in a new way? The main point of this book is to teach all the LA material in an approachable, informal narrative as opposed to formal the theorem-proof approach used in most textbooks. Can serious mathematical topics be introduced using informal language, yet without saying anything outright wrong? Can I trick the reader into learning advanced topics like Fourier transforms and quantum mechanics by making the connections to basic operations explicit? Can I sneakily introduce spaced repetition by covering core ideas several times in the book using different notation and in different contexts?