我正在使用amsmath
包但不断收到以下错误:
\begin{split}
\[
A_R&=\frac{4}{9}+\frac{20}{81}+\frac{100}{729}+\frac{500}{6561}+\dots \\
&=\frac{4}{3^2}+5\times\frac{4}{3^4}+5\times5\times\frac{4}{3^6}+5\times5\times5\times\frac{4}{3^8}+\dots \\
&=\sum_{n=1}^{\infty}5^{n-1}\times\frac{4}{3^{2n}} \\
&=\sum_{n=0}^{\infty}5^{n-1}\times\frac{4}{3^2n+2}} \\
&=\frac{\frac{4}{9}}{1-\frac{5}{9}} \\
&=1
\]
\end{split}
错误是在后面的行检测到的\end{split}
,我不明白为什么。我还得到:
! Argument of \split has an extra }.
! Extra }, or forgotten \endgroup.
答案1
}
该行的最后一行&=\sum_{n=0}^{\infty}5^{n-1}\times\frac{4}{3^2n+2}} \\
不应该在那里。另外,split
环境必须放在里面数学模式,不在外面:
\[
\begin{split}
A_R&=\frac{4}{9}+\frac{20}{81}+\frac{100}{729}+\frac{500}{6561}+\dots \\
&=\frac{4}{3^2}+5\times\frac{4}{3^4}+5\times5\times\frac{4}{3^6}+5\times5\times5\times\frac{4}{3^8}+\dots \\
&=\sum_{n=1}^{\infty}5^{n-1}\times\frac{4}{3^{2n}} \\
&=\sum_{n=0}^{\infty}5^{n-1}\times\frac{4}{3^2n+2}} \\
&=\frac{\frac{4}{9}}{1-\frac{5}{9}} \\
&=1
\end{split}
\]