Hi Showkat,

Sorry to say but to take admission in any NIT for M.Sc. in Mathematics ,the minimum eligibility criteria is B,Sc in Mathematics/B.A, with Mathematics honors.

So after doing B.Tech you cannot take admission in any NIT for masters in mathematics.Well you can do Integrated P.hd after completing you four year B.tech Degree.

Hope this will help,please feel free to ask if you have any further queries.

Thank You.