i want to prepare iit-jee after 12 class.can i attempt 2 chances after 12 class without applying any chances before

no.......................

No u cann't .

U can apply jee in two consecutive years only, one in which u have passed 12th and the other the next year.

If u don't give jee this year(IITJEE-2011) then also u will get only one chance next year(IITJEE-2012).

So don't think from now to prepare after 12th for jee, there is lot of time still left, atleast give your best in the remaining days then after that think about next attempt.............First of all concentrate on the first attempt.

Believe me it's not that easy to drop a year.

So use the remaining days to the fullest.

All the best.......