This book aims to help students of the 3rd grade of high school by reminding them of the necessary mathematical knowledge they need to have from the 1st and 2nd grades of high school in order to better understand the material of the 3rd grade.

The book is divided into the following 10 parts:
1. Real Numbers
2. Trigonometric Numbers
3. Polynomials
4. Exponential and Logarithmic Functions
5. Equations
6. Inequalities
7. Cartesian Plane
8. Systems
9. Functions
10. Geometry

In each chapter, the theory is accompanied by the necessary solved applications in order to clarify all the concepts that are developed.

At the end of the book, there is an index of terms so that the student can easily and quickly locate the sections they wish to study.

Hoping that this effort will achieve its goal, we present this work to the strict judgment of students and fellow educators.