Yes, you must start your jee prepration along with class 11th studies.. and this is what is recommended to most of the students. In JEE therewillbe chapters from Physics, Chemistry, Mathematics, and youwillhave to study class11and 12 syllabus, but theJEEsyllabus is very vast as compared to your school syllabus. So if you prepare for JEE, you can easily crack school exams. You should Have a look at the completeJEE syllabus when you are startingJEE preparation and match it up with your school syllabus. A lot of practice is also required.
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