Matrix t2*K(2) in Subspace 75 with Dimension 8

(K(2) is the second-order Grosse operator)

(-15*t*U)/2 t^2*(4 + U^2/(2*t^2)) 0 -(Sqrt[3]*t*U) -(Sqrt[6]*t*U) 0 -(Sqrt[3/2]*t*U) (Sqrt[3]*U^2)/2
t^2*(4 + U^2/(2*t^2)) (-9*t*U)/2 0 0 0 (Sqrt[3]*t*U)/2 0 (-5*Sqrt[3]*t*U)/2
0 0 -7*t*U -4*t^2 0 -(t*U) 0 0
-(Sqrt[3]*t*U) 0 -4*t^2 -4*t*U -2*Sqrt[2]*t*U 0 0 0
-(Sqrt[6]*t*U) 0 0 -2*Sqrt[2]*t*U -6*t*U -2*Sqrt[2]*t^2 t*U 2*Sqrt[2]*t^2
0 (Sqrt[3]*t*U)/2 -(t*U) 0 -2*Sqrt[2]*t^2 (-9*t*U)/2 (-4*t^2 + U^2)/Sqrt[2] (3*t*U)/2
-(Sqrt[3/2]*t*U) 0 0 0 t*U (-4*t^2 + U^2)/Sqrt[2] -7*t*U -2*Sqrt[2]*t^2
(Sqrt[3]*U^2)/2 (-5*Sqrt[3]*t*U)/2 0 0 2*Sqrt[2]*t^2 (3*t*U)/2 -2*Sqrt[2]*t^2 (-15*t*U)/2