我有这段乳胶代码：
\documentclass{paper}
\usepackage{amsmath}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\begin{document}
\[
W_0=W\\
W_i= ext(W_{i-1}),\ i < \beta
\]
\end{document}
编译时我遇到这些问题：
- 第 8 行：环境方程*未定义。[
- 第 9 行：缺少插入的 $。W_
- 第 11 行：\begin{document} 以 \end{equation*} 结束。]
- 第 11 行：缺少插入 $。]
有什么建议么？
编辑 完整日志：
This is pdfTeX, Version 3.14159265-2.6-1.40.20 (TeX Live 2019/Debian) (preloaded format=pdflatex 2020.2.4) 23 MAR 2020 23:14
entering extended mode
restricted \write18 enabled.
%&-line parsing enabled.
**document.tex
(./document.tex
LaTeX2e <2018-12-01>
(/usr/share/texlive/texmf-dist/tex/latex/paper/paper.cls
Document Class: paper 2008/05/30 1.0l LaTeX document class (wm).
\hours=\count80
\minutes=\count81
(/usr/share/texlive/texmf-dist/tex/latex/base/size10.clo
File: size10.clo 2018/09/03 v1.4i Standard LaTeX file (size option)
)
\beforetitlespace=\skip41
\c@part=\count82
\c@section=\count83
\c@subsection=\count84
\c@subsubsection=\count85
\c@paragraph=\count86
\c@subparagraph=\count87
\exampleindent=\skip42
\c@figure=\count88
\c@table=\count89
\abovecaptionskip=\skip43
\belowcaptionskip=\skip44
\bibindent=\dimen102
)
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsmath.sty
Package: amsmath 2018/12/01 v2.17b AMS math features
\@mathmargin=\skip45
For additional information on amsmath, use the `?' option.
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amstext.sty
Package: amstext 2000/06/29 v2.01 AMS text
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsgen.sty
File: amsgen.sty 1999/11/30 v2.0 generic functions
\@emptytoks=\toks14
\ex@=\dimen103
))
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsbsy.sty
Package: amsbsy 1999/11/29 v1.2d Bold Symbols
\pmbraise@=\dimen104
)
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsopn.sty
Package: amsopn 2016/03/08 v2.02 operator names
)
\inf@bad=\count90
LaTeX Info: Redefining \frac on input line 223.
\uproot@=\count91
\leftroot@=\count92
LaTeX Info: Redefining \overline on input line 385.
\classnum@=\count93
\DOTSCASE@=\count94
LaTeX Info: Redefining \ldots on input line 482.
LaTeX Info: Redefining \dots on input line 485.
LaTeX Info: Redefining \cdots on input line 606.
\Mathstrutbox@=\box27
\strutbox@=\box28
\big@size=\dimen105
LaTeX Font Info: Redeclaring font encoding OML on input line 729.
LaTeX Font Info: Redeclaring font encoding OMS on input line 730.
\macc@depth=\count95
\c@MaxMatrixCols=\count96
\dotsspace@=\muskip10
\c@parentequation=\count97
\dspbrk@lvl=\count98
\tag@help=\toks15
\row@=\count99
\column@=\count100
\maxfields@=\count101
\andhelp@=\toks16
\eqnshift@=\dimen106
\alignsep@=\dimen107
\tagshift@=\dimen108
\tagwidth@=\dimen109
\totwidth@=\dimen110
\lineht@=\dimen111
\@envbody=\toks17
\multlinegap=\skip46
\multlinetaggap=\skip47
\mathdisplay@stack=\toks18
LaTeX Info: Redefining \[ on input line 2836.
LaTeX Info: Redefining \] on input line 2837.
)
(/usr/share/texlive/texmf-dist/tex/latex/base/inputenc.sty
Package: inputenc 2018/08/11 v1.3c Input encoding file
\inpenc@prehook=\toks19
\inpenc@posthook=\toks20
)
(/usr/share/texlive/texmf-dist/tex/latex/base/fontenc.sty
Package: fontenc 2018/08/11 v2.0j Standard LaTeX package
(/usr/share/texlive/texmf-dist/tex/latex/base/t1enc.def
File: t1enc.def 2018/08/11 v2.0j Standard LaTeX file
LaTeX Font Info: Redeclaring font encoding T1 on input line 48.
)) (./document.aux)
\openout1 = `document.aux'.
LaTeX Font Info: Checking defaults for OML/cmm/m/it on input line 7.
LaTeX Font Info: ... okay on input line 7.
LaTeX Font Info: Checking defaults for T1/cmr/m/n on input line 7.
LaTeX Font Info: ... okay on input line 7.
LaTeX Font Info: Checking defaults for OT1/cmr/m/n on input line 7.
LaTeX Font Info: ... okay on input line 7.
LaTeX Font Info: Checking defaults for OMS/cmsy/m/n on input line 7.
LaTeX Font Info: ... okay on input line 7.
LaTeX Font Info: Checking defaults for OMX/cmex/m/n on input line 7.
LaTeX Font Info: ... okay on input line 7.
LaTeX Font Info: Checking defaults for U/cmr/m/n on input line 7.
LaTeX Font Info: ... okay on input line 7.
! LaTeX Error: Environment equation* undefined.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.8 \[
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
! Missing $ inserted.
<inserted text>
$
l.9 W_
0=W\\
I've inserted a begin-math/end-math symbol since I think
you left one out. Proceed, with fingers crossed.
! LaTeX Error: \begin{document} ended by \end{equation*}.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.11 \]
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
! Missing $ inserted.
<inserted text>
$
l.11 \]
I've inserted something that you may have forgotten.
(See the <inserted text> above.)
With luck, this will get me unwedged. But if you
really didn't forget anything, try typing `2' now; then
my insertion and my current dilemma will both disappear.
LaTeX Font Info: Try loading font information for T1+cmss on input line 12.
(/usr/share/texlive/texmf-dist/tex/latex/base/t1cmss.fd
File: t1cmss.fd 2014/09/29 v2.5h Standard LaTeX font definitions
) [1{/var/lib/texmf/fonts/map/pdftex/updmap/pdftex.map}
] (./document.aux) )
Here is how much of TeX's memory you used:
1223 strings out of 494553
13406 string characters out of 6177378
68854 words of memory out of 5000000
4947 multiletter control sequences out of 15000+600000
6391 words of font info for 19 fonts, out of 8000000 for 9000
14 hyphenation exceptions out of 8191
27i,7n,21p,231b,222s stack positions out of 5000i,500n,10000p,200000b,80000s
</home/younes/.texlive2019/texmf-var/fonts/pk/ljfour/jknap
pen/ec/ecrm1000.600pk> </home/younes/.texlive2019/texmf-var/fonts/pk/ljfour/jkn
appen/ec/ecrm0900.600pk></usr/share/texlive/texmf-dist/fonts/type1/public/amsfo
nts/cm/cmmi10.pfb></usr/share/texlive/texmf-dist/fonts/type1/public/amsfonts/cm
/cmmi7.pfb></usr/share/texlive/texmf-dist/fonts/type1/public/amsfonts/cm/cmr10.
pfb></usr/share/texlive/texmf-dist/fonts/type1/public/amsfonts/cm/cmr7.pfb></us
r/share/texlive/texmf-dist/fonts/type1/public/amsfonts/cm/cmsy7.pfb>
Output written on document.pdf (1 page, 40047 bytes).
PDF statistics:
38 PDF objects out of 1000 (max. 8388607)
27 compressed objects within 1 object stream
0 named destinations out of 1000 (max. 500000)
1 words of extra memory for PDF output out of 10000 (max. 10000000)
**文件列表 (\listfiles) **
*File List*
paper.cls 2008/05/30 1.0l LaTeX document class (wm).
size10.clo 2018/09/03 v1.4i Standard LaTeX file (size option)
amsmath.sty 2018/12/01 v2.17b AMS math features
amstext.sty 2000/06/29 v2.01 AMS text
amsgen.sty 1999/11/30 v2.0 generic functions
amsbsy.sty 1999/11/29 v1.2d Bold Symbols
amsopn.sty 2016/03/08 v2.02 operator names
inputenc.sty 2018/08/11 v1.3c Input encoding file
fontenc.sty
t1enc.def 2018/08/11 v2.0j Standard LaTeX file
t1cmss.fd 2014/09/29 v2.5h Standard LaTeX font definitions
***********
提前致谢，
答案1
更新 texlive 后问题消失sudo apt-get install texlive