Buffered feedback circuit analysis
Hint 1: the buffer has zero input current, therefore R3/RL/R3 form a simple voltage divider across Vo+ and Vo-. So you can express V in terms of Vo+

Hint 2: I assume that Vocm is connected to reference ground as it doesn't feature in the circuit. Therefore the differential output voltage, Vod = [(Vo+) - (Vo-)] = 2Vo+

Hint 3: using the input/output relationship for the differential op-amp, Vod = A Vid, where A>>1, you can derive an equation for V in terms of Vi-, Vi+, R1 and R2