MathJax test

When $a \ne 0$, there are two solutions to \(ax^2 + bx + c = 0\) and they are $$x = {-b \pm \sqrt{b^2-4ac} \over 2a}.$$ \(F_n = \lfloor\frac{\psi^n}{\sqrt{5}}\rfloor\), where \(\psi\) is \(\frac{1-\sqrt(5)}{2}\).
To find minimum D-digit \(F_n\) we can set \(F_n = \lfloor\frac{phi^n}{\sqrt(5)}\rfloor < 10^D\).
By taking log on both side, and we get \(n \cdot log(\psi) - log(\sqrt(5)) < D \cdot log(10)\)