Paperback Edition Or Hardcover Edition For ?

I need this book as a textbook, but there are two kinds of this book in Amazon. Although most of the student use the hardcover one, I still wonder if these two edition are same. (I saw the page number which amazon gives is not the same). So could anybody help me to figure this out? Thanks a lot.
(p.s. Please don’t answer something like ‘it usually the same.’ Because I need it as a textbook ^_^)