# How to remove unnecessary spacing in flalign ?

When I try to write the following list of equations, I get too much spacing between certain elements.

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\begin{flalign*}
\end{flalign*}

\end{document}


Whatever I try I can't remove the unnecessary spacing before the inequality sign.

• Why do you add all those \quads? Isn't the default spacing enough? – Bernard Nov 27 '17 at 10:49
• I thought it looked better. However the problem is not there. With or without those \quad the problem remains. – Yohan Obadia Nov 27 '17 at 10:51

You forgot that when there are k columns of alignment, you need 2k-1 &: one for the new column (exceptthe first), and one for the alignment point in this column.

Here are two suggestions:

\documentclass{article}
\usepackage{amsmath}
\usepackage[showframe]{geometry}

\begin{document}

\begin{flalign*}
& \Rightarrow & 1-p(1+\beta) & \geq\frac{c+u}{W} &\\
& \Rightarrow & (1+\beta) & \leq \frac{1}{p}-\frac{c+u}{Wp} &\\
& \Rightarrow & \beta & \leq \frac{1-p}{p}-\frac{c+u}{Wp} & \\
& \Rightarrow & \beta_{\max} & = \frac{1-p}{p}-\frac{c+u}{Wp} &
\end{flalign*}

\begin{alignat*}{2}
& \Rightarrow & \qquad 1-p(1+\beta) & \geq\frac{c+u}{W}\\
& \Rightarrow & (1+\beta) & \leq\frac{1}{p}-\frac{c+u}{Wp} \\
& \Rightarrow & \beta & \leq \frac{1-p}{p}-\frac{c+u}{Wp} \\
& \Rightarrow & \beta_{\max} & =  \frac{1-p}{p}-\frac{c+u}{Wp}
\end{alignat*}

\end{document}


If you want the block of equations to be aligned on the left, you can use the fleqn option from amsmath (in which case all equations will be left-aligned. If you want only some equations to be left-aligned, you can nest athe alignat* environment in a fleqn environment (from package nccmath). The environment can take an optional argument, which is the distance from the left margin (0pt by default).

Here is an example:

\documentclass{article}
\usepackage{amsmath, nccmath}
\usepackage[showframe]{geometry}

\begin{document}

\begin{fleqn}[1em]
\begin{alignat*}{2}
& \Rightarrow & \quad 1-p(1+\beta ) & \geq\frac{c+u}{W}\\
& \Rightarrow & (1+\beta ) & \leq\frac{1}{p}-\frac{c+u}{Wp} \\
& \Rightarrow & \beta & \leq \frac{1-p}{p}-\frac{c+u}{Wp} \\
& \Rightarrow & \beta_{\max} & = \frac{1-p}{p}-\frac{c+u}{Wp}
\end{alignat*}
\end{fleqn}

\end{document}


• I am looking for something with the flalign* command like the first one you suggested. However, I don't want the huge spacing that you got between the \Rightarrow and the rest of the equation... I just need to move the right part of the equation much closer to the left one. The left one should remain aligned left. – Yohan Obadia Nov 27 '17 at 11:11
• I give you a +1 for the k columns explanation. However I can't accept the answer as it is since it does not solve my issue. I will validate it if you can show me a solution that allows to align everything to the left without the huge spacing that you get in your first solution. – Yohan Obadia Nov 27 '17 at 13:09
• Oh! I didn't understand you wanted everything on the left. I suppose you don't want all your equations aligned to the left? – Bernard Nov 27 '17 at 18:32
• @YohanObadia: I've updated my answer with another example. Is that what you want? – Bernard Nov 27 '17 at 18:50
• Yes exactly ! This is not achievable with flalign ? Meanwhile I will use your solution, thanks ! – Yohan Obadia Nov 27 '17 at 19:07