Question

I just an explanation of the second part, Please!!

a) At what level of production will the marginal cost be minimized?

b) At what level of production will the average cost A(x)=C(x)/x be minimized?
C(x)= x^(3)-12x^(2)+48x+98

Answer 1

just plug in your number for x

Answer 2

Well you just take A(x), which is:
C(x)/x = x^2 - 12x + 48 + 98x^(-1)
Take the derivative of A(x):
A'(x) = 2x - 12 - 98x^(-2)

Answer 3

Set that equal to 0, solve for x.

Answer 4

I still don't get the answer.

Answer 5

Yes!

Answer 6

ok.. let's see

Answer 7

By the principle, if Average Cost is Minimum,
<=> Average Cost = Marginal Cost

Answer 8

You've already had Marginal Cost in question a)

Answer 9

I think so, lol! I have 3(x-4)^2 that's for the a)

Answer 10

How do get Marginal Cost?

Answer 11

I follow the examples, sorry!

Answer 12

I believe that is kind of factoring..

Answer 13

for the first two numbers.

Answer 14

No, Marginal Cost is C' (x)

Answer 15

Ohh!!

Answer 16

ok, I got 3x^2-24x+48 right!

Answer 17

Okie, it's just another way of minimum value :)

Answer 18

Simplified:
-> Marginal Cost C'(x) = x² - 8x + 16

Answer 19

Now set Marginal Cost = Average Cost

Answer 20

Ok, that's is my problem..

Answer 21

How you got the the marginal Cost C'(x)? I have it different way.

Answer 22

That's the same thing as this 3(x-4)^2?

Answer 23

Your way's correct!

Answer 24

Ok, Uff!!!

Answer 25

Ok, hold on then!! lol!

Answer 26

How do i set it up? Like this

Answer 27

Like "this" ???

Answer 28

2x^3-12x^2-98=0

Answer 29

Where does it come from?

Answer 30

I gues that the last part, f(x)

Answer 31

You see what i mean, is the way that the explain i don't get it.

Answer 32

It is an online class.

Answer 33

It's extremely confused to solve from the ... middle of a problem !!!

Answer 34

Now I think I must back track from the beginning :/

Answer 35

Ok. How do i set up the Marginal Cost = Average Cost??

Answer 36

So which one do you think is Marginal Cost?

Answer 37

Ok, either yours or mine! 3(x-4)^2

Answer 38

It's the same, but my equation is already expanded and simplify, so use it!

Answer 39

Ok nice!

Answer 40

Which one is Average Cost?

Answer 41

Write them here with "= " in between :)

Answer 42

x=16?

Answer 43

Please show your work, I don't have the talent to read people's mind!

Answer 44

How? Not sure how to do it! :(

Answer 45

What do you mean? Where do you get x = 16???

Answer 46

So please do NOT guess, as I don't guess and trying to help you out here!

Answer 47

I know that's why i am asking you, because i don't know how to do it.. Sorry!

Answer 48

Marginal Cost = Average Cost

Answer 49

ok.

Answer 50

3x^2-24x+48=3(x-4)^2

Answer 51

This is just Marginal Cost equation!
Plug the Average equation to the right side, instead!

Answer 52

No way I gave up!

Answer 53

Did you see the other solver already posted above?

Answer 54

x^2-12x+48+98=0

Answer 55

C(x)/x = x^2 - 12x + 48 + 98/x

Answer 56

It's Average Cost function!

Answer 57

Yes I have that part.

Answer 58

i forgot the x sorry!

Answer 59

Then set Marginal Cost = Average Cost

Answer 60

3x^2-24x+48=2x^3-12x^2-98/x .

Answer 61

C(x)/x = x^2 - 12x + 48 + 98/x

Answer 62

@rocal2 What's so difficult to copy 2 equations down???

Answer 63

It is not difficult, believe me this question is the only one that it is drivie me crazy..

Answer 64

I am not sure what i am doing. That's why i am here!

Answer 65

I keep showing you which one is Average function, and you keep copying down incorrect ???

Answer 66

I am telling that i don't how to solve it...

Answer 67

But that's ok, thanks for trying, and i am sorry to waste your time, I didn't meant to!!

Answer 68

I will go to my school and find someone who can explaine me... Thank you so much!!