NCERT books can be considered as enough for JEE main preparation. But in this case one has to go through each and every line of this book. Many times direct questions are asked from NCERT textbook. If we talk about chemistry section in JEE Main then around 80% of questions are from NCERT. Either it is taken from book directly or it is somewhat twisted. There are three sections in chemistry: organic, inorganic and physical, so the question arises in mind is that possible that one can be totally dependent on NCERT chemistry for each section.
NCERT is completely enough for inorganic chemistry for JEE Main. If you go through inorganic chapters like chemistry in everyday life, biomolecules, hydrogen, alkali and alkaline earth metals, s- block, p- block, d- block and f- block elements from NCERT textbook you can easily score 28- 30 marks. For organic chemistry, the chemistry book of NCERT contains all the reactions which are asked in the JEE main exam but it has missed out on some oxidizing and reducing agents. So, it would be better to read about these reagents from some reference books. For physical chemistry, NCERT has all the formulas and concepts. So, if a JEE aspirant read NCERT thoroughly, one will not have a problem in solving questions of physical chemistry. But it will be better if you have any reference book.
For physics, one cannot suggest you to become completely dependent upon NCERT. One should take help of reference books as well. H C VERMA is one of the highly recommended books. For physics you need some extra learning outside NCERT. Apart from that, you can also read the NCERT exemplar. Going through NCERT exemplar is good for JEE Main.
For math, sometimes the questions may be a little tricky so it is always advised to practice more number of problems as much possible. So apart from reading NCERT solve NCERT exemplar and give mock tests. You should go through other reference books as well for practicing more number of problems.
If you want to crack JEE Main then your first priority should be solving NCERT exemplar before solving any other book. So first read NCERT line by line then solve NCERT exemplar. This will be enough for chemistry. For mathematics and physics you have to read little bit extra also. So, the thing is that NCERT books and PYQs can be enough for JEE main preparation but though it will be better if you take help of reference book for few section. Also take mock tests to boost the confidence. Practice last 10 years question paper of JEE main. You can find them on PracBee app for free.
Hope this helps. All the best.
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