i have completed my board exams.in the leave,what topics should i read.which books are required for preparing for IIT-JEE.how many hours should i read

The board exams are over so must be having lots of time. You should not waste this time. You should start with Agebra in Mathematics. First take a syllabus of IIT JEE which is the best guide.
 
You should start with 6 hours a day now and then you have to increase this to about 10 hours a day.

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