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# (Unresolved) Exercise 8.15

### Problem

Formally define the CDH assumption. Prove that hardness of the CDH problem relative to $$\mathcal{G}$$ implies hardness of the discrete-logarithm problem relative to $$\mathcal{G}$$, and that hardness of the DDH problem relative to $$\mathcal{G}$$ implies hardness of the CDH problem relative to $$\mathcal{G}$$.

### Solution