Let $\displaystyle\int x^3\sin x\,dx = g(x)+C$, where $C$ is the constant of integration. If $8\!\left(g\!\left(\dfrac{\pi}{2}\right)+g'\!\left(\dfrac{\pi}{2}\right)\right) = \alpha\pi^3+\beta\pi^2+\gamma$, $\alpha,\beta,\gamma\in\mathbb{Z}$, then $\alpha+\beta-\gamma$ equals: