Respuesta :
All you have to do is add it could be so simple 8$ + $2 + $2400
The height and side of the box for the maximum volume are 20 feet and 10 feet respectively.
What is area?
Area is the amount of space occupied by a two-dimensional figure.
How to calculate the area of square?
The area of square is the product of the length of each side with itself.
[tex]A = a^{2}[/tex]
Where,
A is the area of square
a is the length of the side of square
What is volume?
Volume is the measure of the capacity that an object holds.
Formula for the volume of cuboid
volume = length × breadth × height
According to the given question
We have
A box with the open top and square base.
Let x be the side of the box. And h be the height of the box
Also, the cost of material for the base is $8 and for side is $2 per square foot.
The total cost of material for the box is $2400
⇒[tex]8x^{2} + 4(2xh) = 2400[/tex]
⇒ [tex]8x^{2} + 8xh = 2400\\[/tex]
⇒[tex]x^{2} + xh = 300[/tex]
⇒ [tex]h = \frac{300-x^{2} }{x}[/tex]
Therefore,
volume of the box
[tex]= x^{2} h[/tex]
= [tex]x^{2} \frac{3000-x^{2} }{x}[/tex]
= [tex]x(300-x^{2} )[/tex]
= [tex]300x - x^{3}[/tex]
for the maximum volume,[tex]\frac{d}{dx}(v)=0[/tex]
⇒ [tex]300 - 3x^{2} =0[/tex]
⇒[tex]300 = 3x^{2}[/tex]
⇒ [tex]x^{2} =100[/tex]
⇒ x = ± 10
⇒ x= 10 feet (x = -10 not possible)
So, h = [tex]\frac{300-100}{10} = 20feet[/tex]
Hence, the height and side of the box for the maximum volume are 20 feet and 10 feet respectively.
Learn more about volume here:
https://brainly.com/question/1578538
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