\[\cos^{ 4} \dfrac{\pi}{7} + \cos^{4} \dfrac{ 3 \pi}{7} + \cos^{4} \dfrac{5 \pi}{7} \]
###### Image Credit: Wikimedia Heptagon by SoluS

If the above expression is equals to \( \dfrac {a}{b} \) where \(a\) and \(b\) are coprime positive.

Find \(a+b\).

×

Problem Loading...

Note Loading...

Set Loading...