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.
Answer:

Step-by-step explanation:
we know that
Applying the Intersecting Secant Theorem

substitute the values

Solve for ED



OK. Here they are:
135,
235,
335,
435,
535,
635,
735,
835, and
935 .
You take 3•4 to get 12, then you add a zero to that and get 120. You then multiply by six and get 720.
Answer:
G
Step-by-step explanation:
I say G because when you look at the bar, the maximum is 100% and G is 20 in total. Therefore, the maximums are the same types and both can be divided by 10.