Question

Give the coordinates of a shape that can be rotated about the y-axis to create a cylinder. Provide an explanation and proof for your answer to receive full credit. Please help.

Answer 1

a rectangle

Answer 2

Yes, thank you. But how do I rotate the rectangle about the y-axis?

Answer 3

take the integral with respect to the y-axis. For example if the rectangle was the region between the y-axis and the line x=5

Answer 4

Yes, thank you. But how do I rotate the rectangle about the y-axis?

Answer 5

I'm not sure what you're asking

Answer 6

Sorry, my computer just acted up and reloaded, sending my last post again. What is an integral?

Answer 7

what subject are you in? I assumed you were doing calculus, but I guess not?

Answer 8

No, I am in Geometry.

Answer 9

to make the cylinder we need to rotate a vertical line around the y-axis.
http://image.tutorvista.com/content/feed/u839/Solid%20of%20revolution.PNG
Basically the y-axis is the center of rotation, meaning it doesn't move, and the line revolves around it 360° in a full circle

Answer 10

So the coordinates are rotating 360 degrees. If my coordinate is (2,0) what would the new coordinate as a result of the rotation?

Answer 11

(2, 0). 360° is all the way around so you end up where you started.

Answer 12

I tend to use revolve and rotate interchangeably. I think revolve would be more accurate here, so where revolving around the y-axis.

Answer 13

Ahh so if my understanding is correct, then I can choose any 4 coordinates as long as they create a rectangle. Undergoing the 360 degree rotation, the transformed coordinates about the y-axis would be exactly the same as the original?

Answer 14

I think we're referring to two different things.