Hey!There.

Both are goods in their own perspective.If you have interest in mathematics and want do research studies in mathematics field then you should move ahead with PhD in mathematics.Aftet having PhD you can become a professor..But you can't go with aeronautical engineering if you doesn't have interest in it as this stream is for such students who are good in Physics and mathematics.If you are really want to pursue Btech from aeronautical engineering then surely you will get good pay package after pursuing it.This stream has good scope and higher employability rates.

Ask if any query..