Question
Find the marginal revenue at x=10 using the equation R(x)=-x^2+80x
Is the answer 60?
Is the answer 60?
Answers
Kuai
R(x) = -x^2 + 80x
R'(x) = -2x + 80
R(10) = -2(10) + 80 = -20 + 80 = 60
Correct
R'(x) = -2x + 80
R(10) = -2(10) + 80 = -20 + 80 = 60
Correct
Lindsay
Yes! Thank you! I do have another question, though. The second part of the problem says to "compare R(11) -R(10) with that result." Does that mean that I derive it before plugging in 11 and 10 or...?
Steve
no, R(11) is just that. No derivative.
It's showing you how the marginal revenue can be approximated by noting the increase in revenue from one point to another.
R(11) = 759
R(10) = 700
∆R = 59, which is pretty close to R'(10)
It's showing you how the marginal revenue can be approximated by noting the increase in revenue from one point to another.
R(11) = 759
R(10) = 700
∆R = 59, which is pretty close to R'(10)