A = 2·(x·(p - x) + x·(x/2) + (p - x)·(x/2)) =
=superficie totale parallelepipedo
A = 3·p·x - 2·x^2
C.N. A'=0----> 3·p - 4·x = 0-----> x = 3·p/4
Il volume vale:
V= x·(p - x)·(x/2)---> V= x^2·(p - x)/2
v = (3·p/4)^2·(p - 3·p/4)/2----> V = 9·p^3/128
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d = diagonale di base= √(x^2 + (p - x)^2)
d = √(2·x^2 - 2·p·x + p^2)
D = √(2·x^2 - 2·p·x + p^2 + (x/2)^2) =
=diagonale parallelepipedo
D = √(9·x^2 - 8·p·x + 4·p^2)/2
C.N. D' = 0
(9·x - 4·p)/(2·√(9·x^2 - 8·p·x + 4·p^2)) = 0
x = 4·p/9
V = (4·p/9)^2·(p - 4·p/9)/2----> V = 40·p^3/729