Saturday

December 20, 2014

December 20, 2014

Posted by **anu** on Friday, January 7, 2011 at 1:36am.

- calculus -
**Reiny**, Friday, January 7, 2011 at 9:02amI will assume that by "most economical" you mean

"minimum cost of material for surface area".

let each side of the end square be x, so the radius for the end circles is also x

let the height be y

SA = 2x^2 + 2πxh

but V = 400

400 = πr^2h

h = 400/(πr^2)

SA = 2x^2 + 2πx(400/(πx^2)

= 2x^2 + 800/x

find d(SA)/dx

set it equal to zero and solve for x

straightforward from here.

**Answer this Question**

**Related Questions**

Math - The Recycling Department of a fast food chain is planning to have a ...

geometry - A cylindrical tin can holding 2 gal.has its height equal to the ...

solid mensuration - A cylindrical tin can holding 2 gal.has its height equal to ...

Math - A cylindrical can is made from tin.If it can be contain 1000 m^3 liquid ...

calculas,math - A cylindrical can is made from tin.If it can be contain liquid ...

Algebra - A manufacturer of tin cans wishes to construct a right circular ...

Algebra - A manufacturer of tin cans wishes to construct a right circular ...

calculus - Use differentials to estimate the amount of tin in a closed tin can ...

Mathes - The radius of the circular base of the larg tin is 5 cm the height is ...

MATH - A tin is a right circular cylinder with a diameter of 6 meters and a ...