This book which is written by hc verma is best for class11 and 12 student. I personally used this book and at initial stage somebody told me that its very tough but I used at starting I felt similar but gradually I noticed that I am getting result. This book made my concept strong . this book not only help to 11 12 student but to competetive also . the type of question are just awesome .they are difficult too but get your basic and concept clear . I also think that theory part should be more. But after all this is best for me and all