When I started my Physics major, I had to complete two advanced Maths courses titled- Mathematical Methods I, II.
My love for Math took off from there. If you ask for books, then I would mention the MP book by Arfken, Weber, Harris. So minimal, yet straight to the point. Consistent and edifying.
I read a different Maths book in HS than what everyone else read. It was a local book, but very well written by prominent Mathematical intellectuals- the kind that write Math columns or act as mentors of syllabus advisory committee. This made a huge difference.
I liked Statistical Mechanics in college. I read Blundell and Blundell for it along with an unusual book as a reference- https://www.amazon.com/Thermal-Physics-Thermodynamics-Statis... .
How Math explains the physical world so prominently blew my mind. I loved it.
I also watched Calculus video from MIT-OCW when in HS.
I switched to Deep Learning after college. How I could actually use Math to build something extremely practical made me love Math even more. This was the true turning point.
I now want to spend three years- part-time, studying higher math by myself. I think it is worth it, and I want to do original, basic research in the Deep Learning space.
While I keep my eye out for resources, I follow these lists-
I can recommend this book for you to read right now-
1. The Joy of X: A Guided Tour of Mathematics from Zero Infinity by Steven Strogatz. A truly remarkable book.
2. How Not to Be Wrong: The Hidden Maths of Everyday Life by Jordan Ellenberg.
YouTube videos from 3blue1brown and Numberphile also increased my love for Maths.
Edit: I read some chapters from Alex Bello's Alex's Adventures in The Numberland. It was fantastic. I can recommend it.
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