Introductory Functional Analysis with Applications

Kreyszig is a well-known author for good reason: his writing is utterly clear and brilliant. He does an excellent job of motivating the techniques and tools he uses in discussion of ideas and concepts, and it'd be hard to ask for a more thorough text.I lament Kreyszig could not have authored books for all my courses, but, for the time being, I'm greatly satisfied with Functional Analysis and Applications.

I can't think of a better place to begin learning functional analysis. The book is ideally suited for undergraduates or beginning graduates who have had one or two semesters of real analysis, linear algebra, and possibly topology. The author seemed extremely lucid with clear worked out examples. Phrases like "it's obvious" or "it should be clear" were not so frequent. It's quite a beautiful subject, with the last chapter providing a nice payoff application in terms of an introduction to quantum mechanics.May be my only complaint was that the exercises seemed mostly five-finger ones. With that said, they should still challenge an undergraduate or beginning graduate, if not force them to re-visit the definitions and basic methods of proof.I've always thought Rudin's "Mathematical Analysis" book deserved the title of "Best Undergraduate Math Text Ever", but this book has made me rethink that position.

The print quality is bad. But no complaints because it's too cheap

A very good self-study book for beginners in functional analysis. Requires understading of undergrad real analysis

This text is for my first course in Functional Analysis.The subject is abstract but enjoyably scientific in flavor; it seems to have many applications outside of pure mathematics.The text is easy enough to read (although some of the proofs are hard to understand) and the exercises are accessible enough that I could recommend it to anyone who has studied Calculus and maybe Linear Algebra.It seems like a book interesting and accessible to students of Physics and Engineering as well as those of Mathematics.

Great book. It was published in the 1980s. Price for such an old book is way too high.

I studied this book for my graduate introduction to functional analysis. It provides a systematic and rigorous approach to the subject. Highly recommend it.

I am about 1/3 way through the text and so far I enjoyed reading the text a lot. The author takes time to explain the theorems and even more importantly emphasizes concepts that are of importance. Excellent book for self study. Highly recommended!