Difference between revisions of "Volume of a Sphere"

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(Created page with "Let's say that we want to find the volume of a sphere of radius <math>r</math> using volumes of revolution.")
 
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Let's say that we want to find the volume of a sphere of radius <math>r</math> using volumes of revolution.
 
Let's say that we want to find the volume of a sphere of radius <math>r</math> using volumes of revolution.
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We know that the equation of a circle of radius <math>r</math> centered at the origin is
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::<math>x^2+y^2=r^2.</math>
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The upper half semicircle is given by: <math>y=\sqrt{r^2-x^2}.</math>
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(insert picture of semicircle)
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Now, we want to rotate the upper half semicircle around the <math>x</math>-axis. This will give us a sphere of radius <math>r.</math>
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(insert pictures)

Revision as of 09:58, 27 August 2017

Let's say that we want to find the volume of a sphere of radius using volumes of revolution.

We know that the equation of a circle of radius centered at the origin is

The upper half semicircle is given by:

(insert picture of semicircle)

Now, we want to rotate the upper half semicircle around the -axis. This will give us a sphere of radius

(insert pictures)