find the dimensions of the right circular cone of least volume that can be circumscribed about a sphere of radius a. let x + 2a = altitude ofthe cone

Question

anonymous · Answer

Do you agree this is the cross section of the situation?
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anonymous · Answer

Maybe not really? I haveno idea

anonymous · Answer

You have a sphere.  Do you know what circumscribed means?

anonymous · Answer

Yes

anonymous · Answer

Okay. Where does the sphere contact the circumscribed cone?

anonymous · Answer

Try drawing it.  Or try this: put your hand in the shape of a cone (make it as if you're about to do finger push-ups) and put a ball in your hand.  Where does the ball touch the hand?

anonymous · Answer

On the sides

anonymous · Answer

Yeah.  Now imagine you sliced your hand in half while holding the ball.  Do you agree that it would look like the cross section I drew up there?

anonymous · Answer

Ignore the gory side-product of this metaphor, please.

anonymous · Answer

Now i got it. And then?

anonymous · Answer

K.  Do you agree that by the definition of circumscribed, the line $l$ in the diagram below only intersects the circle once?
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anonymous · Answer

Yes?

anonymous · Answer

So if it's tangent, do you agree that
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anonymous · Answer

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