LaTeX Forum

\documentclass[12pt,a4paper, BCOR=10mm]{article}
\usepackage[utf8]{inputenc}
\usepackage[german]{babel}
\usepackage[T1]{fontenc}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage[a4paper,
	left=5cm,right=15mm,top=25mm,bottom=25mm,
	showframe
]{geometry}
\author{Madeleine}
\title{Bachelorarbeit}

\begin{document}
\begin{equation}
	P_{1n} = \frac{\exp^{\mu V 1 n}} {\Sigma^ {I _{j=1}} \exp ^{\mu V j n}} = \frac{1}{1+
		\Sigma^{I _ {j=2}} \exp^ {\mu \left(V_{jn} - V_{1n}\right)}}
\end{equation}
\end{document}

\documentclass[12pt,a4paper, BCOR=10mm]{article}
\usepackage[utf8]{inputenc}
\usepackage[german]{babel}
\usepackage[T1]{fontenc}
\usepackage{makeidx}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage[pdftex]{graphicx}
\usepackage{multirow}
\usepackage{tabularx}
\usepackage{setspace}\spacing{1.8}
\usepackage[a4paper, left=5cm,right=15mm,top=25mm,bottom=25mm]{geometry}
\usepackage[backend=bibtex,style=alphabetic, citestyle=authoryear]{biblatex}
\bibliography{Literatur2.bib}
\author{Madeleine}
\title{Bachelorarbeit}

%
\begin{equation}
  P_{1n} = \dfrac{\text{exp}^{\mu V 1 n}} {\Sigma^ {I _{j=1}} \text{exp} ^{\mu V j n}} = \dfrac{1}{1+ \Sigma^{I _ {j=2}} \text{\exp}^ {\mu \left(V_{jn} \minus  V_{1n}\right)}}
\end{equation}
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