HSC Stuff > HSC Mathematics Extension 2

Nagisa Maths Thread

<< < (3/18) > >>

Phy124:
Didn't do spesh so not sure if this is on the course, but how I would have done it using the shell method.

That is

Where in this case is the upper function (translated 1 unit left for the reasons stated in previous posts) minus the lower function over the domain ,, which they have an enclosed area i.e.



edit:


--- Quote from: TrueTears on December 24, 2012, 12:42:40 am ---This volume can be found very easily by the following computation:



Why?

--- End quote ---
Oh yes, you can just multiply the function by (x-1) rather than translating the function left 1, of course :P

TrueTears:

--- Quote from: Clifford on December 24, 2012, 12:46:12 am ---Didn't do spesh so not sure if this is on the course, but how I would have done it using the shell method.

That is

Where in this case is the upper function (translated 1 unit left for the reasons stated in previous posts) minus the lower function over the domain ,, which they have an enclosed area i.e.



--- End quote ---
Correct, using cylindrical shells is what I was referring to, however is there really a need to translate? ;)

Makes the algebra harder, in fact whenever you spin around a different vertical or horizontal line, there is never a need to translate, all you have to do subtract or add the radius/height on.

EDIT: Just saw your edit, yup that's correct Clifford :P

Nagisa:

--- Quote from: TrueTears on December 24, 2012, 12:42:40 am ---This volume can be found very easily by the following computation:



Why?

--- End quote ---

this was my method also but couldnt quite get it to work and i didnt know why lol. I had 4 as the int terminal and radius as (1 - x).

TrueTears:
lol hsc maths is pretty cool ;)

FlorianK:
TT, why do you destroy my working out with a line :(?

Navigation

[0] Message Index

[#] Next page

[*] Previous page

Go to full version