Thanks for the advice! Using the auxiliary equation I obtained: k^2 + 4k + 13 = 0
Therefore, k = (-4 ±√16+52)/2
k1 = 2.213
k2 = -6.123
Θ = Ae^2.123t + Be^-6.123t
I dont think this is correct because I haven't done anything with t=0, Θ=2 and dΘ/dt = 8...