Matrix t2*K(2) in Subspace 39 with Dimension 2

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

(-15*t*U)/2 (I/4)*(I + Sqrt[3])*(8*t^2 + U^2)
(-I/4)*(-I + Sqrt[3])*(8*t^2 + U^2) (-15*t*U)/2