When \(a \ne 0\), there are two solutions to \(ax^2 + bx + c = 0\) and they are \[x = {-b \pm \sqrt{b^2-4ac} \over 2a}.\] \(F(X)=X^n+\sum_{i=1}^n (-1)^i E_i X^{n-i} = \prod_{i=1}^n (X-X_i),\) \[F(X)=X^n+\sum_{i=1}^n (-1)^i E_i X^{n-i} = \prod_{i=1}^n (X-X_i),\] \begin{equation} E = mc^2 \end{equation} In equation \eqref{eq:sample}, we find the value of an interesting integral: \begin{equation} \int_0^\infty \frac{x^3}{e^x-1}\,dx = \frac{\pi^4}{15} \label{eq:sample} \end{equation}