MHB Calculating Volume of a Solid by Subtracting Volumes of Basic Shapes

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The discussion focuses on calculating the volume of a solid by subtracting the volumes of a cylinder and a hemisphere. The user has already calculated the volumes using the formulas for each shape: the cylinder's volume is πa²h and the hemisphere's volume is (2/3)πa³. To find the volume of the solid, the volume of the hemisphere is subtracted from that of the cylinder. The final step involves plugging in the calculated volumes and simplifying the expression. This approach emphasizes the importance of showing progress when seeking help in problem-solving.
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Please solve this problem

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:)
 

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mathlearn said:
Please solve this problem

:)

Good evening and welcome to MHB! :D

We ask that our users show their progress (work thus far or thoughts on how to begin) when posting questions. This way our helpers can see where you are stuck or may be going astray and will be able to post the best help possible without potentially making a suggestion which you have already tried, which would waste your time and that of the helper.

It is also MHB policy to not answer questions which are for credit or for exams.

Can you post what you have done so far?
 
Thank you super Sonic

So far

I calculated the volume of the cyclinder by taking "a" as the radius π(pie)a^2h

and I calculated the volume of the hemisphere (4/3πr^3)

and that was so far
 
Okay, using your formulas, we have the volume of a cylinder having radius $a$ as:

$$V_C=\pi a^2h$$

And the volume of a hemisphere of radius $a$ as:

$$V_H=\frac{2}{3}\pi a^3$$

Now, in order to find the volume of the given solid, we need to take the volume of the cylinder and remove (subtract) the volume of the hemisphere:

$$V_S=V_C-V_H$$

So, plug in for $V_C$ and $V_H$, then factor...what do you get?
 
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