# Cubes and Sixths

Algebra Level 5

Let the complex numbers $$a$$, $$b$$ and $$c$$ be the roots of the equation $$x^3+3x+5=0$$. Find the value of $\frac{a^6-1}{a-1}+\frac{b^6-1}{b-1}+\frac{c^6-1}{c-1}.$

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