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Max and Min problem, need help (1 Viewer)

RHINO7

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A silo in the shape of a cylinder is required to hold 8600m^3 of wheat.


i) Find an equation for the surface area of the silo in terms of the base radius-
 

PC

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First use the data in the question:

V = πr2h
8600 = πr2h
h = 8600/πr2

SO using this value for h, substitute it into the formula for surface area:

S = 2πr2 + 2πrh
S = 2πr2 + 2πr x 8600/πr2
S = 2πr2 + 17200/r
or
S = 2πr2 + 17200r-1

Hope this helps a bit...
 

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