Question 1017

Definite Integrals: Areas and Volumes
2017 Paper 2 Question 4 Variant

Question

(a)
A flat novelty plate for serving food on is made in the shape of the region enclosed by the curve y=x25x+4{y=x^2 - 5 x + 4} and the line 2y=3x3.{2 y = 3 x - 3.} Find the area of the plate.
[4]
(b)
A curved container has a flat circular top. The shape of the container is formed by rotating the part of the curve x=yay2,{\displaystyle x=\frac{\sqrt{y}}{a-y^2},} where a{a} is a constant greater than 1{1}, between the points (0,0){(0,0)} and (1a1,1){\displaystyle \left( \frac{1}{a-1}, 1 \right)} through 2π{2\pi} radians about the y-axis.{y\textrm{-axis.}}
(bi)
Find the volume of the container, giving your answer as a single fraction in terms of a{a} and π.{\pi.}
[4]
(bii)
Another curved container with a flat circular top is formed in the same way from the curve x=yby2,{\displaystyle x=\frac{\sqrt{y}}{b-y^2},} and the points (0,0){(0,0)} and (1b1,1).{\displaystyle \left( \frac{1}{b-1}, 1 \right).} It has a volume two times as great as the container in part (i). Find an expression for b{b} in terms of a.{a.}
[3]

Answer