MATH101 April 2016
Other MATH101 Exams

### Question 8 (b)

Let ${\displaystyle A}$ be the region to the right of the ${\displaystyle y}$-axis that is bounded by the graphs of ${\displaystyle y=x^{2}}$ and ${\displaystyle y=6-x}$. Both parts of this question concern this region ${\displaystyle A}$.

(b) Write down an expression, using horizontal slices (disks), for the volume obtained when the region ${\displaystyle A}$ is rotated around the ${\displaystyle y}$-axis. Do not evaluate any integrals; simply write down an expression for the volume (you don’t need to justify it).

 Make sure you understand the problem fully: What is the question asking you to do? Are there specific conditions or constraints that you should take note of? How will you know if your answer is correct from your work only? Can you rephrase the question in your own words in a way that makes sense to you? If you are stuck, check the hint below. Consider it for a while. Does it give you a new idea on how to approach the problem? If so, try it!

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