Let \( x^* y = x^2 + y^3 \) and \( (x^ * 1) ^* 1 = x^* (1 ^* 1) \). Then a value of \( 2 \sin^{-1}\!\left(\frac{x^4 + x^2 - 2}{x^4 + x^2 + 2}\right) \) is:
If \( \sin^{-1}\frac{\alpha}{17}\ + \cos^{-1}\frac{4}{5}\ - \tan^{-1}\frac{77}{36}\ = 0 ,\; 0<\alpha<13 \), then \( \sin^{-1}(\sin \alpha) + \cos^{-1}(\cos \alpha) \) is equal to:
\( \max\limits_{0 \le x \le \pi} \left\{ x - 2 \sin x \cos x + \dfrac{1}{3} \sin 3x \right\} = \)
