[Tex/LaTex] Cross partial derivatives with LaTeX

equations

I'm trying to write something simple:

Not quite sure how to write out the second term (from the left) in LaTeX. Any suggestions please?

Best Answer

\documentclass{article}

\begin{document}

\[
  \frac{\partial^2 f}{\partial y \, \partial x}
    = \frac{\partial}{\partial y} \biggl( \frac{\partial f}{\partial x} \biggr)
  %  = \frac{\partial}{\partial y} \left( \frac{\partial f}{\partial x} \right)
    = (f_x)_y
    = f_{xy}
    = \partial_{yx} f
\]

\end{document}

There is a difference in the spacing between using a \biggl(...\biggr) and \left(...\right) pair. Your choice, although the former is preferred.

Related Solutions

[Tex/LaTex] Show the Steps Taken to Solve an Equation

You should consider using amsmath:

enter image description here

\documentclass{article}
\usepackage{amsmath}% http://ctan.org/pkg/amsmath
\begin{document}
\begin{align*}
  x^2 + 2x + 1 &= 0 \\
  (x+1)^2 &= 0 \\
  \llap{$\rightarrow$\hspace{50pt}} x &= -1
\end{align*}
\end{document}

[Tex/LaTex] How to show work on binary number addition/conversion

There are probably lots of different ways of doing this- the solution below uses a simple array environment.

screenshot

The only subtle thing is that I've used the optional [t] argument to specify the vertical alignment. I've also used the enumitem to format the enumerate environment to have roman numbers (some might call it overkill).

MWE

\documentclass{article}
\usepackage{enumitem}   % for customizing list environments
\begin{document}

\begin{enumerate}[label*=\roman*.]
  \item $\begin{array}[t]{r}
        2012\\
        -1024\\\hline
        988\\
        -512\\\hline
        476\\
        -256\\\hline
        220\\
        -128\\\hline
        92\\
        -64\\\hline
        28\\
        -16\\\hline
        12
      \end{array}$
    \item $\begin{array}[t]{c|c|c|c}
        11  &   111 &   011 &   100 \\
        3   &   7   &   3   &   4
      \end{array}$
\end{enumerate}
\end{document}

Putting two such calculations side by side

Following the comment, there are lots of ways to put two such arrays side by side. You could use a minipage, but that might require some width calculations, so an easy solution is to use a tabular and then nest the arrays inside