LaTeX Forum

\documentclass{scrartcl}
\usepackage{siunitx}
\sisetup{locale=DE}
 
\usepackage{amsmath}
\usepackage{ziffer}%JB: Was soll das denn?

\begin{document}
\begin{align}
%A_1&=1,12\cdot 10^{-3}-1,44j\notag\\
%A_2&=1,12\cdot 10^{-6}+6,44\cdot 10^{-5}j\\
A_3&=\num{1,12+6.44j}\\
A_4&=\num{1,12+64.4je-6}
\end{align}
\end{document} 

\documentclass{scrreprt}
\usepackage{graphicx}									
\usepackage{siunitx} 
\sisetup{locale=DE}
 
\usepackage{amsmath} 
\usepackage{ziffer} 

\begin{document} 
x

\begin{align}
&A_1=1,12\cdot 10^{-3}-1,44j\notag\\
&A_2=1,12\cdot 10^{-6}+6,44\cdot 10^{-5}j
\end{align}
\end{document}