Written in Swedish, this volume is intended to be a guide for individual study or supervised courses in applied mathematics for physics and engineering students at the undergraduate level. In the first few chapters, MATLAB is used as a calculator. The concept of vectors is then introduced, and these serve as tools for drawing curves. The graphics are used in a direct way to find zeros, extreme points, and limits, so that the relation to elementary arithmetic becomes obvious. By very simple and concrete methods, the reader is guided through algebra, calculus, probability theory and curve fitting, ordinary differential equations, and Fourier analysis. The student can execute the short MATLAB scripts in the example problems, thus gradually becoming acquainted with basic programming. In addition, the Symbolic Math Toolbox is introduced and used to solve examples.