We have to represent the fraction
in two different ways.
Let us multiply the numerator and denominator of the given fraction by '2'.
Therefore, 
Therefore,
is the first way to represent the given fraction.
Now, Let us multiply the numerator and denominator of the given fraction by '3'.
Therefore, 
Therefore,
is the second way to represent the given fraction.
Therefore,
and
are the different ways to represent the fraction
.
<h3>
Answer: 15x^(7/3) - 8x^(7/4) + x + 9000</h3>
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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.