A) Demand function
price (x) demand (D(x))
4 540
3.50 810
D - 540 810 - 540
----------- = -----------------
x - 4 3.50 - 4
D - 540
----------- = - 540
x - 4
D - 540 = - 540(x - 4)
D = -540x + 2160 + 540
D = 2700 - 540x
D(x) = 2700 - 540x
Revenue function, R(x)
R(x) = price * demand = x * D(x)
R(x) = x* (2700 - 540x) = 2700x - 540x^2
b) Profit, P(x)
profit = revenue - cost
P(x) = R(x) - 30
P(x) = [2700x - 540x^2] - 30
P(x) = 2700x - 540x^2 - 30
Largest possible profit => vertex of the parabola
vertex of 2700x - 540x^2 - 30
When you calculate the vertex you find x = 5 /2
=> P(x) = 3345
Answer: you should charge a log-on fee of $2.5 to have the largest profit, which is $3345.
D = 2r => 12.6 = 2*r => r=6.3
A = π*r^2 = (3.14) * (6.3)^2 = (3.14)*(39.69) = 124.6266 which is approximately 124.63
Hope this helps!
Sorry for the chicken scratch
It says as x approaches negative infinity y approaches negative infinity and as x approaches positive infinity y approaches negative infinity
Jeff
3/4 miles in 10 minutes
times 6
9/2 miles in 1 hour
Barbara
13/16 mile in 15 minutes
times 4
13/4 mile in 1 hour. As a result, Jeff is the faster walker and he will wake 5/4 more miles in 1 hour. Hope it help!
Answer:
0.084 IS THE ANSWER
I DONT KNOW HOW TO EXPLAIN IT SORRY