•  Arihant Maths Series

This series by Arihant books is a very good series for preparing for IIT-JEE. In the last many years we have seen that many similar questions from these books have come directly in the JEE Mains paper. These books provide variety of questions of all the concepts, and help in making the students familiar with the pattern of questions asked in JEE papers. This series has both easy and difficult level questions with explained solutions.

  • Cengage Maths Series

This is another very good series of books, which has a good explanation of concept with multiple solved examples after the concept. Thus students can first go through the concept and then solve the examples to check their understanding. Then after each chapter, it has exercises with lots of questions of different difficulty levels. This is indeed a very good option for preparing for JEE. 
The PDF of these books are available in the Maths section under Free Study Material tab.