Math & Science ⇒ Fraction in plain TeX

[tex_eugene]

Hi, I have been trying to use $\frac{abc}{xyz}$ in TeXworks, but I failed to do so. Can someone help me? the error message is:

Code: Select all

This is pdfTeX, Version 3.1415926-1.40.11 (MiKTeX 2.9)
entering extended mode
(C:\Users\Eugene\Desktop\untitled-2.tex
! Undefined control sequence.
<recently read> \frac 
                      
l.2 $\frac
          {a}{b}$
? 

Thanks!!!

[Stefan Kottwitz]

Hi,

welcome to the board!

\frac is a LaTeX command and available by default. I guess you are typesetting with pdfTeX, not pdfLaTeX. Choose the latter, in the TeXworks menu:

pdflatex.png (21.53 KiB) Viewed 5822 times

Stefan

[tex_eugene]

Thanks Stefan,I wonder if I can use it in pdfTex?

[Stefan Kottwitz]

You could define it yourself:

Code: Select all

\def\frac#1#2{{\begingroup#1\endgroup\over#2}}
$\frac{abc}{xyz}$
\end

Stefan

[tex_eugene]

It's done, Thanks very much Stefan!!