Find the number of units x that produce a maximum revinue R.
R=800x-0.2x^2
R=48x^2-0.2x^3
Find the number of unites x that produce the minimum average cost per unit C.
C=1.25x^2+25x+8000
C=0.001x^3+5x+250
find the amounts of advertising that maximizes the profit P. (s and p are measeured in thousands of dollars.) Find the point of diminishing returns.
P= -2s^3+35s^2-100s+200
P=-0.1s^3+6s^2+400