Part a Assume that the height of your cylinder is 6 inches Consider A as a function of r so we can write that as A r 2 2 12 r What is the domain of A r In other words for which values of r is A r defined Part b Continue to assume that the height of your cylinder is 6 inches Write the radius r as a function of A This is the inverse function to A r i e to turn A as a function of r into r as a function of A r A Hints To calculate an inverse function you need to solve for r Here you would start with A 2 r 12 Tr This equation is the same as 2 r 12 r A 0 which is a quadratic equation in the variable r and you can solve that using the quadratic formula You will want to keep A as a variable when you plug the values into the quadratic formula If you want to type in 3 1 in Mobius in text mode you can type in 3 pi 1 x 1 There is x 1 more information in the Introduction to Mobius unit Part c If the surface area is 300 square inches then what is the radius r In other words evaluate r 300 Round your answer to 2 decimal places Hint To compute a numeric square root such as 17 3 you could Use a spreadsheet such as Microsoft Excel or OpenOffice Calc and type in sqrt 17 3 Use a browser to connect to the Internet and type in sqrt 17 3 into a search field Use a calculator The radius is Number inches if the surface area is 300 square inches