5. Find all values of $a$ for each of which the equation

$$
x^{3}+(a-1) x^{2}+\left(a^{3}+3 a^{2}-4 a-8\right) x+(a+2)^{3}=0
$$

has three distinct roots that form a geometric progression (specify these roots).
5. For $a=2$

$$
\frac{3-\sqrt{5}}{2},-1, \frac{3+\sqrt{5}}{2}; \text { for } a=4 \quad \frac{3-\sqrt{5}}{2}, 1, \frac{3+\sqrt{5}}{2} \text {. }
$$

# Answers to Moscow variant 3-2