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Product Multiple

Geometry Level 2

\[ \large (1+\cos A)(1+\cos 3A)(1+ \cos 5A)(1+\cos 7A) \]

What is the value of the expression above if \(A = 22.5^\circ \)?

\[\frac18\] \[\frac12\] \[\frac14\] \[\frac13\]

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