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Prove that: cos20^(@)cos40^(@)cos80^(@...

Prove that:
`cos20^(@)cos40^(@)cos80^(@)=1/8`

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To prove that \( \cos 20^\circ \cos 40^\circ \cos 80^\circ = \frac{1}{8} \), we can follow these steps: ### Step 1: Start with the left-hand side (LHS) We have: \[ P = \cos 20^\circ \cos 40^\circ \cos 80^\circ \] ...
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