Hi,

The eligibility for NDA to join the  Air Force and Naval Wings of National Defence Academy and for the 10+2 Cadet Entry Scheme at the Indian Naval Academy:

Candidates must have passed the Class 12th exam in the 10+2 pattern of schooling or equivalent with Physics and Mathematics administered by a State Education Board or a University.

There will not be any problem while applying to Airforce with applied mathematics as a subject since you only need to prepare mathematics according to the syllabus.