Sunday

January 25, 2015

January 25, 2015

Posted by **Susan** on Saturday, December 4, 2010 at 2:10am.

- calculus -
**Reiny**, Saturday, December 4, 2010 at 1:44pmlet the width be w, and the depth be d

then

S = kwd^2 where k is a constant

but d^2 + w^2 = 144

d^2 = 144-w^2

S = kw(144-w^2)

= 144kw - kw^3

d(S)/dw = 144k - 3kw^2

= 0 for max of S

3kw^2 = 144k

w^2 = 48

w = √48

then d = .....

I will let you finish up.

**Answer this Question**

**Related Questions**

Calculus1 - The strength, S, of a rectangular wooden beam is proportional to its...

Calculus - The strength of a beam with rectangular corss-section is directly ...

Calculus - The strength of a beam with rectangular corss-section is directly ...

calculus - Hi, I'm having trouble with this problem... "If the strength of a ...

math - The stiffness S of a rectangular beam is proportional to its width (w) ...

calculus - A rectangular beam is cut from a cylindrical log of radius 25 cm. The...

Calculus - A rectangular beam is cut from a cylindrical log of radius 30 cm. The...

Calculus - I need help with this question: The strength of a beam with a ...

Math - The following table represents the diameter of the cross section of a ...

Math - The following table represents the diameter of the cross section of a ...