rendered paste body\newcommand{\sys4}[5] {\ifthenelse{\equal{#1}{}}{ %vide premier parametre systeme normal \left\{ \begin{array}{l} #2 \\ #3 \\ #4 \\ #5 \end{array} \right.}{ \begin{array}{rl} ~ & #2 \\ #1 & #3 \\ #1 & #4 \\ #1 & #5 \end{array}}}\newcommand{\sys3}[4] {\ifthenelse{\equal{#1}{}}{ %vide premier parametre systeme normal \left\{ \begin{array}{l} #2 \\ #3 \\ #4 \end{array} \right.}{ \begin{array}{rl} ~ & #2 \\ #1 & #3 \\ #1 & #4 \end{array}}}\newcommand{\sys2}[3] {\ifthenelse{\equal{#1}{}}{ %vide premier parametre systeme normal \left\{ \begin{array}{l} #2 \\ #3 \end{array} \right.}{ \begin{array}{rl} ~ & #2 \\ #1 & #3 \end{array}}}