Answer:
a) Y(x) = {900, x≤30; 900-40(x-30), x>30}
b) T(x) = {900x, x≤30; 2100x-40x², x>30}
c) dT/dx = {900, x≤30; 2100-80x, x>30}
Step-by-step explanation:
a) The problem statement gives the function for x ≤ 30, and gives an example of evaluating the function for x = 35. So, replacing 35 in the example with x gives the function definition for x > 30.

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b) The yield per acre is the product of the number of trees and the yield per tree:
T(x) = x·Y(x)

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c) The derivative is ...

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The attached graph shows the yield per acre (purple, overlaid by red for x<30), the total yield (black), and the derivative of the total yield (red). You will note the discontinuity in the derivative at x=30, where adding one more tree per acre suddenly makes the rate of change of yield be negative.
No.
Step-by-step explanation:
It starts at the bottom (remember if you learned run, then take off to fly.) then the end is longer and higher.
Answer:
5/hypotenuse, the square root of 7/ leg
Step-by-step explanation:
3^2+4^2=25 or 5^2. you use a^2+b^2=c^2. it would be one of the hypotenuses. If the missing number is a leg, you would do 4^2=3^2+x^2. 16=9+x^2, 7=x^2, so you plug in the numbers differently.
The surface area of a sphere is A = 4 π R² .
Sadly, the question doesn't give you 'R', so you have to
back it out of the circumference.
Circumference = π (diameter)
Divide each side by π : Diameter = circumference / π
Radius = 1/2 diameter: Radius = circumference / (2 π)
Area = 4 π R² =
4 π (circumference/2π)² =
4 π (circumference)² / 4 π²
Divide top and bottom by 4π : Area = (Circumference)² / π
Circumference = 37.68 units
Area = (37.68)² square units /π =
<em>451.93 square units</em>