Another Telescoping Series

Geometry Level 5

Find the sum of the following series----

$$\dfrac{\sin^{3}{1}}{1}+\dfrac{\sin^{3}{3}}{3}+\dfrac{\sin^{3}{9}}{9}+\dfrac{\sin^{3}{27}}{27}........\infty$$

The angles are given in radians.

Please do not use wolfram alpha.

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