2 Numerical solution

In section 1, we gave the solution of the quadratic equation. This solution can be put in a computer program as is, but is then likely to suffer from round-off error problems.

The better way to do it is to find only one solution, call it $x_1$, from the given formulae (2), selecting $x_1$ as the solution for which the two term in the top of the ratio have the same sign. Then compute the other solution from

\begin{displaymath}
x_2 = \frac{c}{a x_1}
\end{displaymath} (3)