SOLUTION: If x thousand dollars is spent on advertising brush cutters the amount of brush cutters sold will be determined by the function
B(x) = 2300 + 125/x − 517/x^2 for 3 ≤
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-> SOLUTION: If x thousand dollars is spent on advertising brush cutters the amount of brush cutters sold will be determined by the function
B(x) = 2300 + 125/x − 517/x^2 for 3 ≤
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Question 1114937: If x thousand dollars is spent on advertising brush cutters the amount of brush cutters sold will be determined by the function
B(x) = 2300 + 125/x − 517/x^2 for 3 ≤ x ≤ 12
a. At what rate will sales be changing when $6000 is spent on advertising?
b. At what rate will sales be changing when $9000 is spent on advertising?
c. Are sales increasing or decreasing for the level of advertising expenditure in parts (a) and (b) above?
You can put this solution on YOUR website! B(x) = 2300 + 125/x − 517/x^2 for 3 ≤ x ≤ 12
B(6)=2300-125/6+517/36=2300+20.83-14.36=2306.47
B'(x)=-125x^(-2)+2(517)^x^(-3)
=-125/x^2+1034/x^(-3)
B'(6)=1034/216-125/36=+1.315 or $1315 per brush cutter sold
B'(9)=1034/729-125/81=0.287 or $215 per brush cutter sold.
Both are increasing.
