Answer:
Option A is correct.
The equation = .
Explanation:
Sum of the terms of an arithmetic series is given by
, ......[1]
where n is the number of terms, is the first term and
is the last term.
Given the formula for nth term in the arithmetic sequence is,
for n =1
for n =9
Then, put these values in equation [1] for n =9;
or
Therefore, the equation is;
I have attached a diagram of the triangle described.
We can use any of the trigonometric functions to find angle x. Remember, SOH CAH TOA. And since we're finding the angle, we'll need to use an inverse trigonometric function. For this problem, I'll be using the sine function.
sin(x) = 84 / 85
x = sin^-1(84/85)
x = 81.2026 degrees (feel free to round to however many places you need)
Hope this helps!! :)
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Explanation:
If you know the cost function C(x), to find the marginal cost, we apply the derivative.
Marginal cost = derivative of cost function
Marginal cost = C ' (x)
Since we're given the marginal cost, we'll apply the antiderivative (aka integral) to figure out what C(x) is. This reverses the process described above.
D represents a fixed constant. I would have used C as the constant of integration, but it's already taken by the cost function C(x).
To determine the value of D, we plug in x = 0 and C(x) = 9000. This is because we're told the fixed costs are $9000. This means that when x = 0 units are made, you still have $9000 in costs to pay. This is the initial value. You'll find that all of this leads to D = 9000 because everything else zeros out.
Therefore, we go from this
to this
which is the final answer.