Get Firefox. This is not an ideological statement.
Firefox performs better than IE and Chrome and Safari for the display of mathematics. The reason is that, even without a plugin, it works out of the box with mathematical notation displayed through something called Mathematics Markup Language (MathML). IE used to work well with a plugin by Design Science, but with the tendency of modern browsers to iterate rapidly, the latest versions have outstripped the capability of Design Science to update their plugin. So we recommend Firefox.