Literature
Bibliography
You will probably find a lot of introductory math books in your home country and language.
If you intend to study in Germany - and you are invited to do so - here are some excellent books on engineering math in German for beginners
Wilhelm Kuypers
Mathematik Sekundarstufe II
Einführung Logik, Relationen,, Zahlen
Pädagogischer Verlag Schwann
W. Schirotzek, S. Scholz
Starthilfe Mathematik
Teubner Verlag
K. Meyberg, P. Vachenauer
Höhere Mathematik, 2 Vol.
Springer Verlag