We propose a technique for determining of elastic constants K22 and K33 of induced cholesterics, which is based on studies of the electro-optic characteristics of cholesteric-nematic transition, dielectric properties, and pitch of induced cholesterics. Instead of the linear approximation of experimental dependencies of the threshold fields, we propose to use the hyperbolic and parabolic approximations of experimental data to determine constants K22 and K33 with increased accuracy.