The workbook "Mathematics for Engineers" is aimed at students in engineering disciplines at technical universities. The first volume covers differential and integral calculus of one or more real variables. The concept of the workbook is designed to first present the facts (definitions, theorems, etc.). Numerous remarks and additions prepare, explain, and supplement the facts. Understanding is enhanced through a large number of examples. At the end of each chapter, there are tests and practice problems. The tests allow the reader to check their understanding of the definitions and statements. Through the practice problems, the reader can engage with the material. Solutions are provided for the tests and practice problems. Thus, the workbook requires active participation.