Question #c1f8f

2 Answers
Sep 8, 2017

Volume of bounded area =9π cubic units

Explanation:

First let's consider this within the XY-plane
y=9x2
is the equation for the top half (since the root symbol restricts us to non-negative vales) of a circle with center the origin and radius 9=3
bounding this by y=0 and x=0
implies we are dealing (within the XY-plane) with a quarter circle (whose radius is 3 units)

If we rotate this about the X-axis we will obtain half of a sphere.

The volume of a sphere is V=43πr3

Here the radius, r=3, and we only want half of the sphere.

So
XXXVolumebound region=12×43π×33

XXX=9π (cubic units)

I have solved this way:

Explanation:

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