Volume Q (1 Viewer)

Aerath

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Haha, that's my school's exam and the examiner is our Deputy Principal. :p



I think that's the answer? =\ Maybe?
 

lyounamu

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Aerath said:
Haha, that's my school's exam and the examiner is our Deputy Principal. :p



I think that's the answer? =\ Maybe?
I don't know the answer. But it seems right from here. Thanks.
 

Aerath

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And I feel stupid for not drawing the y = sin-1x curve properly. =\
 

lyounamu

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Aerath said:
And I feel stupid for not drawing the y = sin-1x curve properly. =\
It looks alright. It should look more curly though. (and smooth for extra effect)
 

Aerath

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lyounamu said:
It looks alright. It should look more curly though. (and smooth for extra effect)
Haha, I didn't even try to draw it, I just drew a squiggly line (like they teach you to do when you have something like y = x3lnx), before realising that it's a pretty easy curve. :p
 

hollyy.

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ive never done this...why did you square it at the beginning?
EDIT: i can follow the rest
 

lyounamu

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hollyy. said:
ive never done this...why did you square it at the beginning?
EDIT: i can follow the rest
We square it to get the volume. When you find the volume, you use the formula: pi . integral of (y^2).

Squaring part is an essential element of this working out. Without squaring, you only find the surface area, not the volume.
 

Aerath

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Because when using Volume, it's V = int y2dx. I thought it would make sense to square it too.

There was a question about this in 2U Fitzpatrick...I guess we're meant to know it. Fudge. =(
 

conics2008

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the reason why he squared it because his taking discs... and the area of a disc is piy^2 where y=radius

therefore taking multiple dics = pi S from a-b y^2 dx
 

midifile

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conics2008 said:
the reason why he squared it because his taking discs... and the area of a disc is piy^2 where y=radius

therefore taking multiple dics = pi S from a-b y^2 dx
Yep...

It would make more sense if you had done 4 unit volumes
 

Aerath

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midifile said:
Yep...

It would make more sense if you had done 4 unit volumes
If you referring to me, I'm not quite up to there, yet. :(
 

shadyhaze

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is y = sin-1 x between -1<x<1 and -90<y<90?
but yeah then its just doing table of values with x and y² and using formula, but times everything by pi
where does 4unit come into tht question?
 
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shadyhaze said:
is y = sin-1 x between -1<X<1 p and -90<y<90?<> but yeah then its just doing table of values with x and y² and using formula, but times everything by pi
where does 4unit come into tht question?
the four unit stuffs just the theory behind why we use y2. its because we take slices of discs which each resemble a circle.
 

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