area = 1200 = x^2 + 4 x h
so
h = (1200-x^2)/4x
v = x^2h
v = (1/4)x(1200-x^2)
dv/dx 0 at min or max
0 = x(-2x) + 1200 - x^2
3 x^2 = 1200
x^2 = 400
x = 20
h = 400/80 = 5
v = 400 *5 = 2000
The rectangle box with square base is open at the top. The maximum volume of the box made from 1200 m2 tin,in m3 is:
2 answers
answer will be 4000 . calculation mistake.