1. Comprehensive coverage of NCERT books and syllabus of 11th and 12th standard(english) 4th edition -Arihant publication
2.pearson complete guide to the BITSAT (English)
3.BITSAT explorer 2018 by MTG emotional board, 13practice papers BITSAT 2016 PB 8th edition by G K P.These are the recommended sources to prepare for bitsat.I can suggest you some tips for preparation, so... You go through the syllabus and pattern of the paper clearly as it helps you to guess the difficulty level of the paper to be. Prepare as per the weightages and try to cover important topics .Maintain a notes while preparing and don't forget to revise the things. Take mocks test it helps you to know where you are in the preparation. The link provided consists of sample papers of bitsat just go through it.
Hope this would helps you a little bit. All the best for your exam!!
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