Hi I would need in a document several equations which are aligned as in http://tex.stackexchange.com/a/167908/6941 How can I use the following latex formula in orgmode? --8<---------------cut here---------------start------------->8--- \begin{proof} The proof is a follows: \begin{align} (x+y)^3&=(x+y)(x+y)^2\\ &=(x+y)(x^2+2xy+y^2)\\ &=x^3+3x^2y+3xy^3+x^3.\qedhere \end{align} \end{proof} --8<---------------cut here---------------end--------------->8--- I have effectrively --8<---------------cut here---------------start------------->8--- #+LATEX_HEADER: \usepackage{amsmath} * The equations \begin{equation} \begin{align} (x+y)^3&=(x+y)(x+y)^2\\ &=(x+y)(x^2+2xy+y^2)\\ &=x^3+3x^2y+3xy^3+x^3.\qedhere \end{align} \end{equation} --8<---------------cut here---------------end--------------->8--- but with latex fragment preview (C-c C-x C-l) I only get an empty frame. How can use this align environment in org? I could use --8<---------------cut here---------------start------------->8--- \begin{eqnarray*} \hat{f}(x) & \propto & \sum_{\nu} \frac{|F(\nu)H(\nu)|^2}{|N(\nu)|^2} \frac{G(\nu)}{H(\nu)} e^{\frac{2 \pi i \nu x}{N}}\\ & \propto & \sum_{\nu} \frac{|F(\nu)|^2}{|N(\nu)|^2} H(\nu) H^*(\nu) \frac{G(\nu)}{H(\nu)} e^{\frac{2 \pi i \nu x}{N}}\\ & \propto & \sum_{\nu} H^*(\nu) G(\nu) e^{\frac{2 \pi i \nu x}{N}} \end{eqnarray*} --8<---------------cut here---------------end--------------->8--- but eqnarray is apparently bad (see link above). Thanks, Rainer -- Rainer M. Krug, PhD (Conservation Ecology, SUN), MSc (Conservation Biology, UCT), Dipl. Phys. (Germany) Centre of Excellence for Invasion Biology Stellenbosch University South Africa Tel : +33 - (0)9 53 10 27 44 Cell: +33 - (0)6 85 62 59 98 Fax : +33 - (0)9 58 10 27 44 Fax (D): +49 - (0)3 21 21 25 22 44 email: Rainer@krugs.de Skype: RMkrug PGP: 0x0F52F982