Is it worthy to buy Kaczor's "Problems in Mathematical Analysis" three volumes? I'm looking for a problem book in early math analysis, proof based, one single variable calculus problems, limit, continuity, derivative, integral, Taylor theorem, power series, convergence, divergence, elementary transcendental functions, least upper bounds, intermediate and extreme value theorems.
I find Kaczor problems in math analysis three volume, it seems cover same area that I'm looking for. however, this book has very few reviews, and I don't know if it's worthy to buy them.
Any advice?
 A: 1) The books are by Kaczor and Nowak.
2) The exercises are very difficult: I don't think  there are many universities in the world where students learning analysis could tackle them unhelped.
3) They form one of the best collections of exercises ever.
Another contender for "best collection ever" is the famed two-volume work Problems and theorems in analysis  by Pólya-Szegő.
That justly celebrated work contains, despite the title,  much algebra and was at the research level,  many exercises being extracted  from papers published in prestigious journals.
Kaczor-Nowak is not so advanced.
4) Volume III covers integration and  seems less relevant to what you want.
5) My advice: browse volume II. Buy it if you like it: it costs about  51  dollars in the US . Repeat the procedure for volume I and for volume III, in that order.
Remark
Some economists believe that the price of a Big Mac is a better indicator for purchasing power than currencies.
A Big Mac costs \$4.62 in the US and here is the price in other countries .
If you live in the US for example, you will have to decide if you want to sacrifice eleven Big Macs for volume II.
