Matrix t2*K(2) in Subspace 98 with Dimension 3

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

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