problem

[josh123]

i think i understand this but i am not totally sure you have all helped me out so much so i was hoping yuo could help me on this.

Suppose that the total profit in hundreds of dollars from selling x items is given by P(x)= -x^2 + 8x -12 Find the marginal profit at x = 4.

I dont think it is a negative profit. However I got $200 and my friend got $400. i can see how it would be both after looking at both ways. Which one should we use?

 

[stapel]

I got $200 and my friend got $400.

Please reply showing the steps you used to get your answer. If your friend would like, you could include his steps also, and we can review them both.

Thank you.

Eliz.

 

[iamtoostinky]

Hey Josh long time no see. I got $200

 

[tkhunny]

I can think of a way that the answer is $0.00

That's one of the joys of mathematics. It's really not up to pollsters to find the right answer. It's up to definitions, axioms, rules, logic, and consistent calculation (among other things).

What really is needed is your working definitions of "Marginal Profit". Does you book, teacher, or friend offer a DEFINITION?

Just for the record, it appears that your friend found the TOTAL profit for x = 4, not ANY definition of Marginal Profit.