For JEE Mains, is it better to buy separate books for each topic or 1 big book with all topics?

@ lingesh 
its better if u will go for separate books , beacuse that will be easy and convinient for study . 
for that reason the coaching institutes are providing separate books for jee prep . 
but for reference purpose u can go for 1 big book , but thats nt recommended . 
that is in case u ar doing self study without dlp then . 
and almost a through study of ncert and some advance concept will clear your mains . 
ALL THE BEST ..