Bisection method and Muellers method added

documents/math-minimal-distance-to-cubic-function/quadratic-case-2.3.tex

@@ -2,5 +2,8 @@ One solution is
 \[x = \frac{(1-i \sqrt{3}) \alpha}{\sqrt[3]{12} \cdot t}
      -\frac{(1+i\sqrt{3}) t}{2\sqrt[3]{18}}\]
 
-The verification of this case is pretty much the same as for
+The complex conjugate root theorem states
+that if $x$ is a complex root of a polynomial $P$, then its
+complex conjugate $\overline{x}$ is also a root of $P$.
+The solution presented in this case is the complex conjugate of
 case 2.2.