[Tex/LaTex] Horizontal alignment of equation and text

alignhorizontal alignment

I want to make a list of Quantum Mechanics formula like the format of the following picture. But I am confused about how to make the equations align to the left while the text to the right. Usually, if I use environment like, Align or Equation, the equation will be at the center.

I know I can use fleqn package, but it does not align the equations to the left enough as wee see from the picture I attached. My thought to approach this is to usefleqn, then put in the align environment, then use a bunch of \qquad to align for the text part, which is on the right side of the page. But I think this is silly.

Can anyone give me an example of this format? Or does anyone know if there are some cool packages for me to use so that my formula list would look as nice as this one?

enter image description here

Best Answer

Or you can use the flalign* environment provided by the amsmath package:

\documentclass{article}
\usepackage{amsmath}
\usepackage[per-mode=symbol]{siunitx}
\usepackage[english]{babel}
\usepackage{blindtext}% dummy text
\begin{document}
\begin{flalign*}
  &c=\frac1{\sqrt{\epsilon_0\mu_0}}=\SI{3e8}{\m\per\s} &&\text{speed of light}\\
  &\epsilon_0=\SI{8.85e-12}{C^2\per \N\m^2} &&\text{permittivity in vacuum}\\
  &\mu_0 =\SI{4\pi e-7}{\N\per\A^2} &&\text{permeability in vacuum}
\end{flalign*}
\blindtext
\end{document}

enter image description here

Related Solutions

[Tex/LaTex] Right flush text in math environment

In many situations, a comment can be added in the following way:

\begin{align*}
A &= B && \text{(because pigs fly)} \\
  &= C && \text{(since donkeys are not pigs)} \\
  &= D && \text{(because I say so)}
\end{align*}

so that the comments are (left) aligned to each other. However, your case is different: the comment would be only in the last two lines and the fifth one is quite long. The fifth line makes it hard to set the comments so they stick out as such.

Probably the most amenable solution is to defer the comments to the text below the alignment. These are tough decisions, anyway. What about this?

\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{align*}
\makebox[2.8em][l]{$\displaystyle P(X_l=x_l,\ldots ,X_{l+k}=x_{l+k})$} \\
  &= \int_0^1 f(x_l)\cdots f(x_{l+k})\,dp\\
  &= \int_0^1 \prod_{i=1}^k p^{1\{x_i=1\}}(1-p)^{1\{x_i=0\}}\,dp\\
  &= \int_0^1 p^t(1-p)^{k-t}dp\\
  &= \int_0^1 p^{t+1-1}(1-p)^{k-t+1-1}\,dp\\
  &= \dfrac{\Gamma(k-t+1)\Gamma(t+1)}{\Gamma(k+2)}\int_0^1\dfrac{\Gamma(k+2)}{\Gamma(k-t+1)\Gamma(t+1)} p^{t+1-1}(1-p)^{k-t+1-1}\,dp\\
  &= \dfrac{\Gamma(k-t+1)\Gamma(t+1)}{\Gamma(k+2)} \\
  &= \dfrac{t!(k-t)!}{(k+1)!}
\end{align*}
Notice that the last integral is $\Gamma(t+1,k-t+1)$ and $k$ is an integer.
\end{document}

enter image description here

[Tex/LaTex] switch between left and right alignment in multiline equation

I supposed you're in two-column mode, and, if I understand well your requirements, they can be satisfied with an aligned environment nested in the outer align* (with a single alignment column). However, I also propose another solution, based on multlined:

\documentclass[twocolumn]{article}
\usepackage{mathtools}

\begin{document}

\begin{align*}
  & p_\text{very\;long\;function}(x) = \\
  & \phantom{{}={}} \begin{aligned}[t]\int f_\text{very long integral terms}(x)\\
 \mathcal{N}(x; 0, \sigma^2)\, dx
 \end{aligned}\\
  & = 2
\end{align*}

\begin{align*}
  & p_\text{very\;long\;function}(x) \\
  & = \begin{multlined}[t]\int f_\text{very long integral terms}(x)\\
 \mathcal{N}(x; 0, \sigma^2)\, dx
 \end{multlined}\\
  & = 2
\end{align*}

\end{document}

Best Answer

Related Solutions

[Tex/LaTex] Right flush text in math environment

[Tex/LaTex] switch between left and right alignment in multiline equation

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