Newton's Method for optmization

PBJinx
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This is less a homework problem and more conceptual help for a homework problem

I have been given the information for a revenue equation and a cost equation

I set up Newton's Method with



XN+1=\frac{revenue-cost}{the derivative of the top}


where both revenue and cost are determined by price

what I would like to know is that my thinking is right with this set up. The root that I solve for is the price of maximization for the price.
 
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PBJinx said:
what I would like to know is that my thinking is right with this set up. The root that I solve for is the price of maximization for the price.

You didn't explain what your thinking was, you only gave a formula. The formula that you gave makes no sense to me.
 
"the price of maximization for the price" doesn't seem to make much sense. Did you mean "the price of maximization for the profit"? The reason I ask is because profit is obviously defined as (revenue - cost) and it appears you have the ratio: profit/(derivative of profit).

First, note that you're missing an x_n term. Remember if you want to find a root for f, i.e., a p such such that f(p) = 0, Newton's method tells you to look at a sequence of the form x_(n+1) = x_n - f(x_n)/f'(x_n).

But if you are trying to maximize profit, I think you are making a mistake on a conceptual level. If f is the profit function defined by (revenue - cost), you're not trying to find a price at which profit is zero (though certainly there are many microeconomic situations where this would be of interest). Rather you need to find p such that f'(p) = 0.
 
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