  We present results of numerical calculations of electronic states of an
exciton and a trion in a CdTe quantum well at magnetic fields up to 150T. The
exciton state and the trion states were computed using a variational procedure.
We estimated the binding energy of the trion in a singlet state with the
z-component of angular momentum L_z=0, as well as the binding energy of the
trion in a triplet state with L_z=-1. Recent experimental results show that
even up to 44T the binding energy of negative trion in a singlet state is
bigger than in a triplet state. We show that at a critical field B_c=65T the
two binding energies cross and above B_c the binding energy of the trion in a
triplet state is bigger than in the singlet state.
