# Using MathJax in the forum (testing)

@jeremydouglass has recently enabled MathJax for this forum. MathJax allows formulae to be shown as if written in a maths context. So something like x^4+y^3-x^2*y=0 can be displayed inline like this x^4+y^3-x^2*y=0 or displayed like this

x^4+y^3-x^2*y=0

For simple formulae simply enclose the equation between dollar signs $…$ to make it inline with text or display by gating with $$…$$ e.g.
$$x^4+y^3-x^2*y=0$$

If you want to use the dollar symbol in your discussion then you need to put back-slash in front like this
\$. In this context the backslash is called the escape character and says that the character immediately following should be treated literally. For more complicated formulae there is a sophisticated markup which I will try and demonstrate here when I get a chance but this guide looks quite good. EDIT: the this post has been edited based on comments regarding the double dollar syntax provided by @jeremydouglass in the next post. 5 Likes Thanks so much for suggesting and looking into this, @quark. The $$ setting is enabled, but it looks like they are gate fields that need to be on their own line: $$ x^4 + y^3 - x^2 * y = 0 $$ x^4 + y^3 - x^2 * y = 0 It seems fussier than markdown, and I sometimes see the re-render hang in the editor preview window… possibly also due to slow render time? But elegant output. > It can also be mixed with block quotes. >$$ > x^4 + y^3 - x^2 * y = 0 > $$> like this.  It can also be mixed with block quotes… x^4 + y^3 - x^2 * y = 0 …like this. 2 Likes Thanks @jeremydouglass that’s great I will edit earlier posts 1 Like In another discussion the poster added this image to represent the derivative of another function In MathJax this looks like y' = {-4x^2 + 2xy\over 3y^2 - x^2} and the markup to do it is$$ y’ = {-4x^2 + 2xy\over 3y^2 - x^2}$\$

3 Likes