This is an example:

Marginals for the exponential function and log function from Excel models y = de" then y' = abe The marginal sales in week x is y'. Ex: Assume y =14000e then y' =14000(.002)e"?* = 28e" and in week 50, the rate of change in sales is y' = 28023 =28el =30.94 . Y=alnx+b then y'= a X The marginal sales in week x is y'. 1600 1600 Ex: y=1600Inx+9000 then y' = and in week 50, the rate of change in sales is y' = = 32 . X 50 Note: Also compute the marginal for models in other weeks to see the rates of change then.\f(Dry Goods) Boxed Foods 2002-2003 Data Sales in $ $5,000.00 $4,500.00 y =51 163x + 495.86 54,000.00 R3 = 0.7491 $3,500.00 $3,000.00 Sales 52,500.00 52,000.00 $1,500.00 $1,000.00 $500.00 50.00 10 20 30 40 50 60 70 80 90 Weeks