Wednesday

April 16, 2014

April 16, 2014

Posted by **kieran** on Monday, October 1, 2012 at 10:31pm.

- Calculus -
**Reiny**, Monday, October 1, 2012 at 11:04pmmake a sketch

let the base be x by x, and the height be y

so x^2 y = 32

y = 32/x^2

SA = 2x^2 + 4xy

= 2x^2 + 4x(32/x^2)

= 2x^2 + 128/x

d(SA)/dx = 4x - 128/x^2 = 0 for a min of SA

4x = 128/x^2

4x^3 = 128

x^3 = 32

x = 32^(1/3) or appr 3.175

y = 32/3.175^2

Well , what do you know, it happens to be a perfect cube.

**Related Questions**

Calculus - A closed box is to be a rectangular solid with a square base and ...

calculus - the dimensions of a closed rectangular box are measured as 30 in, 40 ...

algebra - true or false?The surface area of an open rectangular box is the same ...

calculus - a rectangular piece of cardboard that measures 4 by 3 inches is to be...

Math - The tree faces of a rectangular solid have areas 6,10, and 15. If the ...

math - A toy baseball bat comes with 3 plastic balls in a box that is a ...

math - A rectangular solid has a base with length 6 cm and width 5 cm. If the ...

math - A toy baseball bat comes with 3 plastic balls in a box that is a ...

Math 117 - 1.) A rectangular solid and a circular cylinder have the same volume ...

optimization calculus - sandy is making a closed rectangular jewwellery box with...