Using multiple calculus books at the same time......

[Alpharup]

Many people advise that we should learn concepts from only one book as using too many books lead to confusion. I have Spivak, Apostol and Kuratowski for Rigorous calculus. When I first read Apostol, I had a hard time understanding. After doing some problems in Spivak, I find the same in apostol easy. For example, Apostol first introduces integration but I could not follow the proof part before. Now, able to read and do proofs, I am able to follow Apostol.
My primary aim is to solve Spivak and read Apostol or other books just for insight. Will such an approach be useful? I feel using different books give multi-intuitive feel.

 

[QuantumQuest]

In my opinion, you can and must study from different books. This works very good, if one book has harder exercises that help grasp concepts better, if the author perspective in one book is not the one to give you deep understanding of a concept, so you have to look into another book and also in a more straightforward complimentary fashion between two books: in parallel. If you have a good grasp of a concept from some book, then you go on. In general, you can use educational sources in parallel, in every conceivable way that you judge to be to your advantage. There is no real reason for confusion. The only reason that causes confusion, is to be under stress and this is something you must always fight.