feedback BJT ac analysis
Without R3, that circuit would be guaranteed to self-servo (self-regulate) into a non-saturated mode of biasing, with a linear operating point. Particularly if the ratio of Rbase to Rcollector were about 100 (many transistors have beta near 100), you'd have a bias_point of VDD/2 which permits maximum +- voltage swings on the collector.

BUT

With R3, its hard to say that circuit is in linear (non_sat) biasing.

If the transistor has very high beta, then R1 (50Kohm) needs little voltage across it to provide adequate base current, and the junction of the two collector resistors needs to be near the collector voltage or the devices enters saturation.