Answer:
<u><em>Dimension of box:-</em></u>
Side of square base = 10 in
Height of box = 5 in
Minimum Surface area, S = 300 in²
Step-by-step explanation:
An open box with a square base is to have a volume of 500 cubic inches.
Let side of the base be x and height of the box is y
Volume of box = area of base × height
Therefore,
It is open box. The surface area of box, S .
Put
![S(x)=x^2+\dfrac{2000}{x}](https://tex.z-dn.net/?f=S%28x%29%3Dx%5E2%2B%5Cdfrac%7B2000%7D%7Bx%7D)
This would be rational function of surface area.
For maximum/minimum to differentiate S(x)
For critical point, S'(x)=0
Put x = 10 into
y = 5
Double derivative of S(x)
at x = 10
![S''(10) > 0](https://tex.z-dn.net/?f=S%27%27%2810%29%20%3E%200)
Therefore, Surface is minimum at x = 10 inches
Minimum Surface area, S = 300 in²