Hey Ratnam,

Choosing applied mathematics along with Physics, Chemistry and other relevant subjects in your Class 11 will not affect your eligibility in JEE Advanced which is given to get admission in IITs. All what matter is, you need to clear JEE Mains with a good percentile where you have to score well in Physics, Chemistry and Mathematics. They will not ask you whether you had basic math/applied mathematics.

So, stay strong with your preparations and be focused on life to get into IITs.

Best of Luck.