Hi Manu...'You are hitting two birds by one Stone.' Anyways, JNU ( Delhi)- Jawahar Lal Nehru University do not offer Undergraduate course except few foriegn language courses and now B.Tech in computer science and engineering has started. So presently there is no scope for you in JNU ( Delhi) , you can apply for P.G and Research in JNU after your Graduation. Now comes JNU ( Jaipur) - In Jaipur National University you can pursue your Maths ( Hons.).Minimum eligibility to appear for this course is 10+2 or intermediate with minimum 45% marks and English as a compulsory subject in +2, from recognized board or Counsil. Admission Screening is done on the basis of merit and interview.

Hope your query is resolved.

All the best.