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  •  » Surface Area and Volume of Spheres, Cylinders, and Cones

#26 2013-11-05 08:31:45

bobbym
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

Hi;

I am getting 6.20403 using the formula I gave you, so I would say they are the same.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#27 2013-11-05 09:07:23

rogerwaters
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

Alright, sounds good. But could you write out the second equation with the formula you gave me so I could present it completely as my work?
After that, we'll move on to number 3


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#28 2013-11-05 12:07:09

bobbym
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones



That is is up there.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#29 2013-11-05 18:58:00

rogerwaters
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

Alright thanks! So let's move to number 3


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#30 2013-11-05 19:05:19

bobbym
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

I am getting 6 for that.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#31 2013-11-05 19:07:09

rogerwaters
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

What formula did you use?


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#32 2013-11-05 19:10:12

rogerwaters
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

oh! I know why it didn't lead to the same result in number 2! Because they ask for the length not area!!
You might wanna check that!


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#33 2013-11-05 19:14:12

bobbym
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

Was the answer wrong?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#34 2013-11-05 19:14:59

rogerwaters
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

I did not submit it. I need to find all of the answers first.


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#35 2013-11-05 19:25:41

bobbym
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

I used this formula:



where n is the number of sides which is 6.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#36 2013-11-05 19:27:28

rogerwaters
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

That's for number 3 right?


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#37 2013-11-05 19:28:41

rogerwaters
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

But the given only tells me that the radius is 6, how did you get the side?
I'm really confused


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#38 2013-11-05 19:32:48

rogerwaters
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

Oh oh!!! If the radius is 6, then the side is equal 6 right?

So that is my answer: If the radius is equal to 6, then the side is equal to 6 as well.

I also got number 4:

4. If a hexagon has a radius (center to point of angle) of 6, what is the area of the hexagon?
First we find the area of one triangle:
area(t) = r^2 sqrt3 /4
area(t) = 6^2 sqrt3 /4
area(t) = 36 x sqrt3 /4
area(t) = 36 x .433021
area(t) = 15.588756

area(h) = 6 x 15.588756
area(h) = 93.53


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#39 2013-11-05 19:39:36

bobbym
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

I plugged into the formula



You are correct for 4.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#40 2013-11-05 19:55:10

rogerwaters
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

Alright! Could you check 4 for me?

And here are my answers for number 5 and 6?

5. If a hexagon is resting on a flat side, and has a total height of 18, what is the length of each side of the hexagon?
A = 9^2 x 6 * tan x (180/6)
A = 280.59

Now that I have the area, I have to find the side where s = side of the hexagon.

3 (√3 /2) x S^2  = 280.59
s^2 = 280.59 x 2 / 3 x √3
s^2 = 561.18 / 5.196152
s^2 = 107.99
s = 10.39




6. If a hexagon is resting on a flat side, and has a total height of 18, what is the area of the hexagon?
a = 9^2 x 6 * tan x (180/6)
a = 280.59


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#41 2013-11-05 20:10:18

bobbym
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

4)Correct.

There is an easier way to do 5.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#42 2013-11-05 20:17:41

rogerwaters
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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

What is the easier way?


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#43 2013-11-05 20:20:36

bobbym
Administrator

Online

Re: Surface Area and Volume of Spheres, Cylinders, and Cones

A formula can be created by using the others, it is:


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#44 2013-11-05 20:24:09

rogerwaters
Full Member

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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

Okay but is the formula I used still correct? Because that's the way the teacher gave it to me.
And what about 6?


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#45 2013-11-05 20:26:41

bobbym
Administrator

Online

Re: Surface Area and Volume of Spheres, Cylinders, and Cones

I would say yes.

What is #6?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#46 2013-11-05 20:27:37

rogerwaters
Full Member

Offline

Re: Surface Area and Volume of Spheres, Cylinders, and Cones

6. If a hexagon is resting on a flat side, and has a total height of 18, what is the area of the hexagon?
a = 9^2 x 6 * tan x (180/6)
a = 280.59


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#47 2013-11-05 20:39:48

bobbym
Administrator

Online

Re: Surface Area and Volume of Spheres, Cylinders, and Cones

That is correct, you could also use,


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#48 2013-11-05 20:40:53

rogerwaters
Full Member

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Re: Surface Area and Volume of Spheres, Cylinders, and Cones

Alright now here's the really tough one, it's worth 4 points.

7. Problem solver (worth 4 points): Come up with a way to find the area and volume of a football. Include in your answer a way to acquire any necessary measurements without cutting or otherwise destroying the football. Also include all necessary formulas to implement your idea. (You don't need to find actual numbers, just outline the method in step by step detail--think of all the measurements you'll need to acquire and how you'll get them.)


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters

#49 2013-11-05 20:45:34

bobbym
Administrator

Online

Re: Surface Area and Volume of Spheres, Cylinders, and Cones

http://upload.wikimedia.org/wikipedia/commons/0/00/Ellipse_axis2.png



You will have to fill in the details.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#50 2013-11-05 20:47:19

rogerwaters
Full Member

Offline

Re: Surface Area and Volume of Spheres, Cylinders, and Cones

Alright, but what are 'a' and 'b' equal to?


I think there are things in my story that have helped my creativity. Your father being killed, for instance, is one of the best things that could happen to a kid if he's going to write poetry or songs.
-Roger Waters
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