This article discusses handling math fonts by means of standard LaTeX, as well as using the amsmath and bm packages....begin{equation} 2 \ sum_{j = 1} ^ {z} j = \ frac{z(z + 1)}{2} 3 \ end{equation}...begin{equation} 6 \ sum_{j = 1} ^ {z} j = \ frac{z(z + 1)}{2} 7 \ end{equation}...