Writing Volume as a Function of Height for an Open Box

AI Thread Summary
To find the volume of an open box made from a 24 cm square piece, squares of side length x are cut from each corner. The volume V as a function of height x can be expressed as V = x(24 - 2x)², which simplifies to V = 4x² - 96x + 576. The domain of this function is limited by the constraints of the box, specifically 0 < x < 12. The discussion emphasizes understanding the transition from area to volume for a rectangular prism rather than a cube.
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Homework Statement



An open box of maximum volume is to be made from a square piece of material 24 centimeters on a side (24-2x) by cutting equal squares from the corners and turning up the sides. The table shows the volumes V (in cubic centimeters) of the box for various heights, x (in centimeters).

(x, V): (1,484), (2,800), (3,972), (4,1024), (5,980), (6,864)

If V is a function of x, write the function and determine its domain.



The Attempt at a Solution



I'm completely stuck on this. I tried recreating the table values by using the volume of a cube formula, but that didn't work. If anyone could give me a nudge in the right direction that would be helpful, thanks.
 
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M83 said:

Homework Statement



An open box of maximum volume is to be made from a square piece of material 24 centimeters on a side (24-2x) by cutting equal squares from the corners and turning up the sides. The table shows the volumes V (in cubic centimeters) of the box for various heights, x (in centimeters).

(x, V): (1,484), (2,800), (3,972), (4,1024), (5,980), (6,864)

If V is a function of x, write the function and determine its domain.

The Attempt at a Solution



I'm completely stuck on this. I tried recreating the table values by using the volume of a cube formula, but that didn't work. If anyone could give me a nudge in the right direction that would be helpful, thanks.
What cubic function do you get for the volume of the box ?
 
The problem tells you that the base is a square that has side length 24- 2x. What is the area of the base? How do you go from "area of base" to "volume"?
 
HallsofIvy said:
The problem tells you that the base is a square that has side length 24- 2x. What is the area of the base?

For a square the area would be the square of the side length.

A= (24-2x)(24-2x)
= 576-48x-48x+4x²
= 4x²-96x+576

HallsofIvy said:
How do you go from "area of base" to "volume"?

Would you cube the side length?
 
M83 said:
For a square the area would be the square of the side length.

A= (24-2x)(24-2x)
= 576-48x-48x+4x²
= 4x²-96x+576



Would you cube the side length?

Why on Earth would you do that? If I have a box whose base has area 10 m2 and whose height (= sides) are 2 m, what is the volume (in units of m3)?

RGV
 
M83 said:
I'm completely stuck on this. I tried recreating the table values by using the volume of a cube formula, but that didn't work.

That's because you don't have a cube to begin with, you have a rectangular prism ("box"). You do know that the volume of a rectangular prism is V = lwh (l = length, w = width, h = height), right?
 
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