If the top half of the ellipse x 2 /a 2 +y 2 /b 2 = 1
Question:
If the top half of the ellipse x2/a2 +y2/b2 = 1 is revolved about the x-axis, the result is an ellipsoid whose axis along the x-axis has length 2a, whose axis along the y-axis has length 2b, and whose axis perpendicular to the xy-plane has length 2b. We assume that 0 < b < a (see figure). Use the following steps to find the surface area S of this ellipsoid.
a. Use the surface area formula to show that
b. Use the change of variables u = cx to show that
c. A table of integrals shows that
d. If a and b have units of length (say, meters), what are the units of S according to this formula?
e. Use part (a) to show that if a = b, then S = 4πa2, which is the surface area of a sphere of radius a.
Step by Step Answer:
Calculus Early Transcendentals
ISBN: 978-0321947345
2nd edition
Authors: William L. Briggs, Lyle Cochran, Bernard Gillett