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September 19, 2014

September 19, 2014

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.

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