Prove that: `\ cos 20^0cos 40^0cos 80^0=1/8`

Explanation

To prove that \( \cos 20^\circ \cos 40^\circ \cos 80^\circ = \frac{1}{8} \), we can follow these steps:

### Step 1: Write the Left-Hand Side (LHS)
We start with the expression:
\[ \text{LHS} = \cos 20^\circ \cos 40^\circ \cos 80^\circ \]

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