Although Fractional Frequency Reuse (FFR) is a good solution for Inter-Cell Interference (ICI) problem, combined FFR and beamforming can be utilized for more improved cellular system performance. In this paper, we consider a hexagonal cellular network, where we derive the Downlink (DL) worst case Signal to Interference Ratio (SIR) closed form formula for three different beamforming techniques (horizontal, vertical, and 3D) combined with sectored FFR. Furthermore, the derived SIRs formulas are used to get Spectral Efficiency (SE) as well as channel capacity in terms of several parameters. Also, we derive an accurate closed form formula for inner radius based on the proposed analytical model including a correction factor. Simulation results show that the proposed analytical method is in good agreement with those obtained through simulations and more accurate than previously published analytical treatments. The same treatment can be applied for other FFR techniques.