You can use GeoGebra to find unit cost and profit if you have the revenue and the cost function. GeoGebra automatically plots the graphs of these functions, too!
GeoGebra Instruction 1
Algebra View and Graphics View under View in Menu. Algebra View as R(x) = <revenue function> and press Enter. Algebra View as C(x) = <cost function> and press Enter. U(x) = C(x)/x, then press Enter. P(x) = R(x) - C(x), then press Enter.