我怎样才能分解这个等式并使其以双列格式看起来美观:
\begin{align}
G=-\frac{\sum_{k=0}^{N}A_{nk}\left(2\frac{(2\frac{q_{sm}}{q^{mex}}-1)^{k+1}
(k+1)}{q^{kex}(2\frac{q_{sm}}{q^{mex}}-1)}-\frac{2k(1-\frac{q_{sm}}
{q^{mex}})}{(q^{kex}(2\frac{q_{sm}}{q^{mex}}-1)^{1-k})}+\frac{2kq_{sm}}
{(q^{kex})^2(\frac{q_{sm}}{q^{mex}}-1)^{1-k}}+\frac{4kq_{sm}(1-\frac{q_{sm}}
{q^{mex}})(1-k)}{(q^{kex})^2(2\frac{q_{sm}}{q^{mex}}-1)^{1-k}(2\frac{q_{sm}}
{q^{mex}}-1)}\right)}{nF}
\end{align}
答案1
像这样?(请注意,我扩大了一些圆括号,用花括号替换了最外面的圆括号,并用数学罗马字呈现了下标和上标项。)
\documentclass[twocolumn]{article}
\usepackage{amsmath}
\begin{document}
\hrule % just to illustrate width of textblock
\begin{align*}
G&=-\frac{1}{nF}\sum_{k=0}^{N}A_{nk}\Biggl\{
2\frac{\bigl(2\frac{q^{}_{\mathrm{sm}}}{q^{\mathrm{mex}}}-1\bigr)^{k+1}(k+1)}{
q^{\mathrm{kex}}\bigl(2\frac{q^{}_{\mathrm{sm}}}{q^{\mathrm{mex}}}-1\bigr)}\\
&\qquad-\frac{2k\bigl(1-\frac{q^{}_{\mathrm{sm}}} {q^{\mathrm{mex}}}\bigr)}{
q^{\mathrm{kex}}\bigl(2\frac{q^{}_{\mathrm{sm}}}{q^{\mathrm{mex}}}-1\bigr)^{1-k}}\\
&\qquad+\frac{2kq^{}_{\mathrm{sm}}}
{\bigl(q^{\mathrm{kex}}\bigr)^2
\bigl(\frac{q^{}_{\mathrm{sm}}}{q^{\mathrm{mex}}}-1\bigr)^{1-k}}\\
&\qquad+\frac{4kq^{}_{\mathrm{sm}}\bigl(1-\frac{q^{}_{\mathrm{sm}}}
{q^{\mathrm{mex}}}\bigr)(1-k)}
{\bigl(q^{\mathrm{kex}}\bigr)^2
\bigl(2\frac{q^{}_{\mathrm{sm}}}{q^{\mathrm{mex}}}-1\bigr)^{1-k}
\bigl(2\frac{q^{}_{\mathrm{sm}}}
{q^{\mathrm{mex}}}-1\bigr)}\Biggr\}
\end{align*}
\end{document}
附录:您应该考虑进行替换$Q=q_{\mathrm{sm}}/q^{\mathrm{mex}}$
,这将大大简化(并澄清)四行公式的外观。(您显然可以自由选择其他符号代替Q
。)此外,它看起来像是取共同的因素2
并将其放在求和之外。
\documentclass[twocolumn]{article}
\usepackage{amsmath}
\begin{document}
\hrule % just to illustrate width of textblock
\bigskip\noindent
Set $Q=q_{\mathrm{sm}}/q^{\mathrm{mex}}$. Then
\begin{align*}
G&=-\frac{2}{nF}\sum_{k=0}^{N}A_{nk}\biggl\{
\frac{(2Q-1)^{k+1}(k+1)}{q^{\mathrm{kex}}(2Q-1)}\\
&\qquad-\frac{k(1-Q)}{q^{\mathrm{kex}}(2Q-1)^{1-k}}\\
&\qquad+\frac{kq^{}_{\mathrm{sm}}}
{(q^{\mathrm{kex}})^2 (Q-1)^{1-k}}\\
&\qquad+\frac{2kq^{}_{\mathrm{sm}}(1-Q)(1-k)}
{(q^{\mathrm{kex}})^2(2Q-1)^{1-k}(2Q-1)}\biggr\}
\end{align*}
\end{document}
答案2
这可行,但我还要删除一些嵌套的\frac
s 并将其替换为a / b
。
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{multline}
G=-\frac{1}{nF}\sum_{k=0}^{N}A_{nk}\Biggl(2\frac{(2\frac{q_{sm}}{q^{mex}}-1)^{k+1}
(k+1)}{q^{kex}(2\frac{q_{sm}}{q^{mex}}-1)}-\frac{2k(1-\frac{q_{sm}}
{q^{mex}})}{(q^{kex}(2\frac{q_{sm}}{q^{mex}}-1)^{1-k})}\\+\frac{2kq_{sm}}
{(q^{kex})^2(\frac{q_{sm}}{q^{mex}}-1)^{1-k}}+\frac{4kq_{sm}(1-\frac{q_{sm}}
{q^{mex}})(1-k)}{(q^{kex})^2(2\frac{q_{sm}}{q^{mex}}-1)^{1-k}(2\frac{q_{sm}}
{q^{mex}}-1)}\biggr)
\end{multline}
\end{document}