Calculating Surface Area by Rotating a Curve - How to Find the Surface Area?

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To find the surface area obtained by rotating the curve y = 1 + 4x^2 from x = 0 to x = 8 about the y-axis, one should consider dividing the area into horizontal slices. Each slice's surface area depends on its slope, which is determined by dy/dx. The next step involves calculating the surface area for these slices and then integrating over the specified range. This approach is similar to calculating volumes of revolution. Understanding surface integrals is essential for solving this problem effectively.
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Homework Statement


Find the area of the surface obtained by rotating the curve
y= 1+4 x^2
from x=0 to x = 8 about the y-axis.


Homework Equations





The Attempt at a Solution

 
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Hi

How did you try to solve it? Or don't you know how to start?
 
Not sure how to start it.
Any assistance would be greatly appreciated.
 
Is this multidimensional calculus course?

If it is, how is surface interagrals defined?

(post in relevant HW-section in the future, this is not introductory physics)
 
Tranquility13 said:
Find the area of the surface obtained by rotating the curve
y= 1+4 x^2
from x=0 to x = 8 about the y-axis.

Hi Tranquility13! :smile:

This is like the one about volumes.

again, divide it into horizontal slices at distance y above the x-axis, with height dy (so the slope is dy/dx).

what is the surface area of this slice (remember, it depends on the slope)?

get that, and then we'll do the integral. :smile:
 
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