Biased inverting amplifier

This circuit takes an input signal, range -1 to 1 V, and transforms it to a range of 0 - 5 V. This is done by using an amplififcation of K = 2.5, and a bias voltage of V_bias = 5 V * R4/(R3+R4). V_out = -K*V_in + (1+K)*V_bias