  We present a study of the generalized second law of thermodynamics in the
scope of the f(R,T) theory of gravity, with R and T representing the Ricci
scalar and trace of the energy-momentum tensor, respectively. From the
energy-momentum tensor equation for the f(R,T) = R + f(T) case, we calculate
the form of the geometric entropy in such a theory. Then, the generalized
second law of thermodynamics is quantified and some relations for its obedience
in f(R,T) gravity are presented. Those relations depend on some cosmological
quantities, as the Hubble and deceleration parameters, and on the form of f(T).
