# A geometry problem by Akshat Sharda

Geometry Level 4

$\sin \dfrac{\pi}{7}\sin \dfrac{3\pi}{7}\sin \dfrac{5\pi}{7}$ If the value of the expression above is in the form $$\dfrac{\sqrt{a}}{b}$$, where $$a$$ and $$b$$ are positive integers and $$a$$ is square free, find $$a+b$$.

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