A cuboid has a rectangular cross section where the length of the rectangle is equal to twice its width x cm. THe volume is 81 cm^3. a) show that the total length L cm of the cuboid is given by L=12x+162/x^2
Volume=81 cm3
b=81/2x2
L=4x+4(2x)+ 4(b)
L=4(x)+4(2x)+4(81/2x2)
L=12x+ 162/x2
BT
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