The TR curve of a monopoly firm is given by the equation
TR=−q2+12q−20, where TR is in millions of dollars
At what level of output is the revenue maximized?
6
The TR equation is given as TR=−q2+12q−20
This is the equation of an inverted parabola. We can rearrange the equation in the following manner.
TR=−q2+12q−20TR=(−q2+12q−36)+36−20 (add and subtract 36)TR=−(q2−12q+36)+36−20TR=−(q−6)2+16
The term −(q−6)2 is always less than or equal to zero.
Hence, TR is maximum when this term is zero i.e. when q=6.