I do not like this question for some reason. I think it is the word rotation and then this 2D line graph.
The question tells us to rotate the rectangle in the graph around the x-axis.
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If you 360 degree rotate the shape you will get a circle. Take a shape and rotate it 360 degrees along any axis at constant speed, and you get a circle.
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However, the question asks us to find the volume of the three-dimensional shape formed by ..... rotating ....
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So I guess let us imagine we are inside of a Minecraft world, where everything is square and circular rotation is a dream.
So at this point I have tried, and my brain is not computing. I typed the question into Google to better understand.
Then I started building an answer but it was more complex than before Google.