I am a student who has just finished high school. I can easily handle IB level differentiation, integration and complex numbers.
I am interested in learning about the Fourier Transform. I am looking for a book, maybe one from a first year university course, which explains the Fourier Transform from the very basics, expanding the concept of Fourier Series and exploring the Fourier Transform from a mathematical perspective.
I read in some other forums that this book was advised for beginners. However, I had trouble following the theory in the book. I feel like the book did not provide the solid background of the Fourier Transform I was looking for.
I would highly appreciate if anyone could advise me on a good book I could use.
I read mostly Springer books. You can try "Classical Fourier Analysis".
However, I do not think one book is ever sufficient to learn a subject thoroughly. Read also books about linear algebra as they explain concept about orthonormal basis, which is important for discreet Fourier transform. Do not hesitate to research from other sources including this website.
n.p. I always find it weird that most schools teach Fourier transform first and then its inverse (some of them do not teach the inverse at all). I learned inverse Fourier first and it made me understand better why we use Fourier transform.