This is a sandbox

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  & = \pi\bigg(\Big(16 \cdot 2 - \tfrac{8}{3} \cdot 2^3 + \tfrac{1}{5} \cdot 2^5\Big)-\Big(16 \cdot -2 - \tfrac{8}{3} \cdot (-2)^3 + \tfrac{1}{5} \cdot (-2)^5\Big)\bigg) \\ wiki