If you're looking for a PDF version of the book, I can suggest a few options:
Moving beyond basic arithmetic into De Moivre’s Theorem and the geometry of the complex plane.
For decades, students transitioning from high school arithmetic to university-level theoretical mathematics have faced a common hurdle: the "abstraction gap." While applied mathematics deals with tangible problem-solving, pure mathematics requires a shift in mindset—into the worlds of logic, proof, sets, and structures.