Hi Roshan,

You have done wrong, the mathematics questions which are asked in NDA Exam are of 11th and 12th level and are solely based on 11th and 12th syllabus only. Now, Mathematics also has a dedicated section for Mathematics questions. Without having knowledge of Mathematics of class 11th and 12th, I bet you will not be able to clear the NDA exam as no matter how good you score in General Knowledge section, you will fail if you are not able to clear cut-off of any of the one section.

Refer here for more info - https://competition.careers360.com/articles/nda-exam-analysis

Feel free to ask doubts in the Comment Section.

I hope this information helps you.

Good Luck!