Folosind relatiile lui Viete obtinem:
[tex]\displaystyle x^2-6x+6=0\\
x_1+x_2=-b/a=6\\
x_1\cdot x_2=c/a=6\\
E= \frac{x_1}{x_2} + \frac{x_2}{x_1} = \frac{x_1^2+x_2^2}{x_1\cdot x_2} =\\
=\frac{(x_1+x_2)^2-2x_1x_2}{x_1\cdot x_2}= \frac{6^2-2\cdot 6}{6} =4[/tex]
