1.
Let f(x)=1+sin2xcos2x4sin2xsin2x1+cos2x4sin2xsin2xcos2x1+4sin2xf(x) = \begin{vmatrix} 1+\sin^2 x & \cos^2 x & 4\sin 2x \\ \sin^2 x & 1+\cos^2 x & 4\sin 2x \\ \sin^2 x & \cos^2 x & 1+4\sin 2x \end{vmatrix}, then the maximum value of f(x)f(x) is -