On the relation between the holomorphic prepotential and the quantum moduli in SUSY gauge theories

We give a simple proof of the relation AanF = &bl (Tr #2), which is vaiid for N = 2 super-symmetric QCD with massless quarks. We consider SU( NC) gauge theories as well as SO( NC) and SP ( NC). An analogous relation which corresponds to massive hypermultiplets is written down. We also discuss the generalizations to N = 1 models in the Coulomb phase.