Abi-Khuzam Inequality

Theorem
Let $\triangle ABC$ be a triangle.

Then:
 * $\sin A \cdot \sin B \cdot \sin C \le k A \cdot B \cdot C$

where:
 * $A, B, C$ are measured in radians
 * $k = \paren {\dfrac {3 \sqrt 3} {2 \pi} }^3 \approx 0 \cdotp 56559 \, 56245 \ldots$