I would highly recommend the Little Mathematics Library series of Mir Publishers. Some of the titles in the series that will be particularly relevant for you are:
- A. G. Kurosh - Algebraic Equations of Arbitrary Degrees
- A. I. Markushevich - Areas and Logarithms
- P. P. Korovkin - Inequalities
They do cover more material than may be required from the point of view of your exams, but they are wonderful to read nonetheless.
Since you mentioned that you want to learn as much as possible, I wouldn't mind adding a few general references that will surely interest you. Try:
- Courant and Robbins - What is Mathematics?
- Ian Stewart - The Foundations of Mathematics
- Ravi Vakil - A Mathematical Mosaic: Patterns and Problem Solving
In fact, it was largely thanks to Ravi Vakil's book that I decided to take up mathematics for my higher studies when I was completing high school.
All the very best.