# Break a long math equation and keep its aesthetic

I would like to replicate the following equation

Unfortuntanely, the following MWE does not seem to work because: (i) I cannot write the brace ({}) symbols in math mode and (ii) because I do not know how to break the equation and keep its aaesthetic.

 \documentclass[]{article}
\usepackage{amsmath}
\begin{document}
\section{Equations}
$$PMV=0.303e^{-0.036M}+0.028\Bigg[(W-M)-3.05.10^{-3}[5733-6.99(M-W)-p_{a}]-0.42[(M-W)-58.15] -1.7.10^{-5}M(5867-p_{a})-0.0014M(34-t_{a}) -3.96.10^{-8}.f_{cl}[(t_{cl}+273)^{4}-(\overline{t_{r}}+273)^4]-f_{cl}.h_{c}(t_{cl}-t_{a}) \Bigg]$$
\end{document}


How can I replicate the above equation?

• Would it be terrible to make the braced component 4 lines long? If that's allowed, I'd realign at minus signs, shifting the last element from the first line, keeping the width the same as the original second line, and ending with the last element (the one with no numeric multiplier) on a line by itself. (I have no available tex installation at the moment, hence a comment, not an answer.) – barbara beeton Sep 11 at 13:24

I squeezed the operator spacing slightly in the bracketed term

I think this does what you ask, although the layout seems a bit confusing to me, if I understand its meaning correctly it would be clearer not to use the large brackets and let the terms wrap over several lines at the outer level.

 \documentclass[]{article}
\usepackage{amsmath}
\begin{document}
\section{Equations}
\begin{multline}
\mathit{PMV}=0.303e^{-0.036M}+0.028\\
\Biggl[\medmuskip=2mu
\begin{gathered}
(W-M)-3.05.10^{-3}[5733-6.99(M-W)-p_{a}]-0.42[(M-W)-58.15]\\
-1.7.10^{-5}M(5867-p_{a})-0.0014M(34-t_{a})\\
-3.96.10^{-8}.f_{cl}[(t_{cl}+273)^{4}-(\overline{t_{r}}+273)^4]-f_{cl}.h_{c}(t_{cl}-t_{a})
\end{gathered}
\Biggr]
\end{multline}
\end{document}

• Thanks. The layout does look strange indeed – Fonde Lapatrie Sep 11 at 7:13
• @FondeLapatrie oh also I noticed that I used \Biggl[ (based on the code you supplied, but the image you show uses \{ not [ but that would be trivial to change. – David Carlisle Sep 11 at 7:56

I propose this other solution, with the Bmatrix environment mathtools and various small improvements:

\documentclass[]{article}
\usepackage{amsmath,mathtools, nccmath}
\usepackage{siunitx}

\begin{document}

\section{Equations}

\begin{fleqn}\sisetup{exponent-product =\,}
\begin{aligned} & PMV =0.303\,e^{-0.036M}+0.028 \times{}\\ &\mathrlap{\begin{Bmatrix}(W-M)-\num{3.05 e-3}[5733-6.99(M-W)-p_{a}] \\ \mkern-5mu -0.42[(M-W)-58.15]-\num{1.7 e-5}M(5867-p_{a})-\num{1.4e-4} M(34-t_{a})\!\! \\ -\num{3.96 e-8}.f_{cl}[(t_{cl}+273)^{4}-(\overline{t_{r}}+273)⁴]-f_{cl}.h_{c}(t_{cl}-t_{a}) \end{Bmatrix}} \end{aligned}
\end{fleqn}

\end{document}
`