Аннотация:Two sum rules are derived, relating moments of the spectral functions of the vector and axial-vector currents. If it is assumed that the $\ensuremath{\rho}$ and $A1$ mesons dominate these moments, then their masses must be in the ratio $\frac{{m}_{A1}}{{m}_{\ensuremath{\rho}}}=\sqrt{2}$, in very good agreement with experiment.
