Stage 1 Introductory Algebra

Introductory Algebra:
Complex number, polynomials, matrix, system of equation, Gaussian elimination, vector space, linear transformation, etc. T.M. Aposotol's Calculus Vol. 1 in the calculus sections also introduce topics that is relevant to this area.

A few Americans (exchanged to Sydney) in my third year abstract algebra class told us they couldn't follow because they haven't learnt much complex number. In order to have fun with linear algebra and complex variables in stage 2, it's better to learn complex number now.