Sketching graphs for volume integration (1 Viewer)

Boonyak

Member
Joined
Feb 15, 2012
Messages
222
Gender
Male
HSC
2012
Hey guys im having trouble sketching it how can i learn this is there anywhere on the net or some sort of trick. I know its not essential but apparently it is of great help :)
 

Shadowdude

Cult of Personality
Joined
Sep 19, 2009
Messages
12,146
Gender
Male
HSC
2010
Umm, what questions are you having trouble with? We can't help you specifically if you tell me you're struggling but don't give me a problem you're struggling with.
 

Boonyak

Member
Joined
Feb 15, 2012
Messages
222
Gender
Male
HSC
2012
Well in general i get confused when the teacher says anything like y=x^2 is spun around the x-axis than he sketches this idont get what is meant by spun around the axis :S
 

Shadowdude

Cult of Personality
Joined
Sep 19, 2009
Messages
12,146
Gender
Male
HSC
2010
So you draw y = x^2. Now think of an axis coming out of the page and you're rotating the curve around that axis. So you get sort of a funnel thing...

It's hard to explain in words, maybe someone else will come along with pretty pictures.
 

Boonyak

Member
Joined
Feb 15, 2012
Messages
222
Gender
Male
HSC
2012
Thanks still confused but just wonderin like is it something i need for question like will i cme across questions that need sketches
 

Shadowdude

Cult of Personality
Joined
Sep 19, 2009
Messages
12,146
Gender
Male
HSC
2010
The sketches will help you figure out what you're doing. It's like doing those "Person moves this much north, that much east, this other quantity south" without a diagram.
 

Boonyak

Member
Joined
Feb 15, 2012
Messages
222
Gender
Male
HSC
2012
The sketches will help you figure out what you're doing. It's like doing those "Person moves this much north, that much east, this other quantity south" without a diagram.

F**CK !! I NEED TO LEARN IT LOL, do u have to sketch with spin or can i jst do a normal sketch omg !
 

Carrotsticks

Retired
Joined
Jun 29, 2009
Messages
9,494
Gender
Undisclosed
HSC
N/A
F**CK !! I NEED TO LEARN IT LOL, do u have to sketch with spin or can i jst do a normal sketch omg !
You don't need to actually draw it as if its 3D.

Try to use your imagination to visualise the solid formed after revolving it.
 

Timske

Sequential
Joined
Nov 23, 2011
Messages
794
Gender
Male
HSC
2012
Uni Grad
2016
if u dont understand this you are scrwed
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top