A cylinder has dimensions: diameter = 4x+2 and height = 4. Work out the volume of this cylinder. Give your answer in terms of x

The volume of a cylinder = (pi).r².hAs the diameter is given in the question, we need to halve it to get the radius --> r = (4x+2)/2 = 2x+1This means the volume of the cylinder = (pi).(2x+1)².4
First we need to expand the radius term:(2x+1)² = (2x+1)(2x+1) <-- Using the FOIL method (First, Outers, Inners, Lasts) we expand this to 2x2x + 2x1 +2x1 + 11 = 4x²+ 4x + 1
which means that the volume of the cylinder = (4x²+ 4x + 1) * pi * 4 = 16.pi.x² + 16.pi.x + 4.pi