Definite integrals

Question code: 32

Question 0905

The region R{R} is bounded by the curve y=4x2e2x{y=4 x^2 \mathrm{e}^{ 2 x }}, the line x=12{x = \frac{1}{2}} and part of the x-axis{x\textrm{-axis}} between 0{0} and 12{\frac{1}{2}}. Find

(i)

the exact area of R,{R,}
[5]

(ii)

the numerical value of the volume of revolution formed when R{R} is rotated completely about the x-axis,{x\textrm{-axis,}} giving your answer correct to 3 decimal places.
[2]
Answer

(i)

(12e1) units2.{\left(\frac{1}{2} \mathrm{e} - 1\right) \textrm{ units}^2.}

(ii)

1.724 units3.{1.724\textrm{ units}^3.}
Question code: 32