Monopolist Profit Maximization with Elasticity Calculation

[econ67]

Homework Statement

A monopolist faces demand y=96-4p and has total costs c=10y.
a) derive the marginal cost and marginal revenue functions.
b) what is the profit-maximizing output and price for this monopolist?
c) Suppose p=10 and MR=5, calculate the elasticit.

Any feedback would be greatly appreciated.

Homework Equations

The Attempt at a Solution

 

[danago]

Do you know the definition of marginal cost and marginal revenue?

 

[econ67]

I have an idea of what they mean, but I am having a hard time finding them for this problem.

 

[vela]

So what do they mean? Show us what attempts have you made to figure them out.

 

[econ67]

What i did to find the marginal revenue was divide the derivative of the total revenue by the derivative of the quantity function. d(96p-4p^2)/d(96-4p)=96-4p/-4=-24+p. Thats what i got for the marginal revenue.

For the marginal cost, i divided the derivative of the cost function by the derivative of the quantity function. 10/-4 was the result i got for the marginal cost function.

 

[vela]

Can you state in words what marginal cost is and what marginal revenue is? I can't tell if you don't have a clear concept of what those quantities are or if you just don't know how to represent them mathematically.