Hey Lilas,
Understanding Marginal Cost
Marginal cost is a fundamental concept in economics and business. It represents the cost of producing one additional unit of a good. In mathematical terms, it's the derivative of the total cost function with respect to the quantity of goods produced. This derivative gives us the rate of change of the total cost with respect to a small change in quantity.
The Cost Function:
Our cost function is C(q)=q^2(sqrt(q)-2), where q is the quantity of items produced. This function tells us the total cost of producing q items.
Calculating Marginal Cost
To find the marginal cost, we need to differentiate C(q) with respect to q.
The Cost Function: C(q)=q^2(sqrt(q)-2)
We have our cost function C(q), and we can break it down into two parts for the product rule:
f(q) = q^2
g(q)= sqrt(q)-2
Product Rule: f(x)g(x)=f'(x)g(x)+f(x)g'(x) (we will sub in q for x in this case)
The product rule states that the derivative of a product of two functions
f(q) and g(q) is f'(q) g(q)+f(q) g'(q).
Differentiation Steps
Differentiate f(q)=q^2 : nx^n-1 where n=2 and n-1=1
The derivative f'(q)=2q.
Differentiate g(q)=sqrt(q)-2 : sqrt(q) is the same as q^1/2: nx^n-1 where n=1/2 and n-1=-1/2
The derivative g'(q)=1/(2sqrt(q))
Apply the Product Rule: (plug and play at this point)
C'(q)= f'(q) g(q)+f(q) g'(q)
C'(q)= (2q)(sqrt(q)-2)+(q^2)(1/(2sqrt(q)))
Simplify:
Simplify the expression to get the marginal cost.
Let's carry out these steps to find the marginal cost.
Using the f(x) and g(x) format and applying the product rule, the marginal cost MC(q) is calculated as follows:
MC(q)=(5/2)(q^3/2)-4q
I hope this helps and you can start to understand how this all works. If you have any questions feel free to book an appointment so we can go over this more in depth.
Regards,
John

John T.
12/19/23
Lilas H.
Thank you very much. I deeply appreciate the time you took to answer to explain this so clearly and easily. I never thought of breaking it into f(q) and g(q) it makes much more sense this way. I am considering finding a tutor for I am lacking a bit in my math course. However, I wanted the explanation of this question urgently for I have a test coming up and while practicing some questions, I stumbled across this one and I simply couldn't come up with the correct solution. There is also another question I am struggling a bit to understand although I am hoping I will eventually figure out the solution. I would like to reach out to you if I hopefully decide to take some lessons here. Again, thank you.12/19/23