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poke smot!
floccinocci floofinator



Registered: 01/08/03
Posts: 5,248
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Help bail me out! (of calculus)
#19255485 - 12/10/13 01:41 PM (10 years, 1 month ago) |
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I've been ill for a few days, is my current excuse for waiting till the day before the test to try out the practice test.
I don't know where else to turn, and school (and tutoring center) is closed due to snow, shit.
I'm hoping someone here will be able to lead me in the right direction.
<img style="max-width:640px;" src="https://proxy.mind-media.com/proxy.php?url=https%3A%2F%2Fproxy.mind-media.co%3Cwbr%3Em%2Fproxy.php%3Furl%3Dhttps%253A%252F%252Fdl%3Cwbr%3E.dropboxusercontent.com%252Fu%252F50%3Cwbr%3E778677%252FScreenshot%252520-%25252012%3Cwbr%3E102013%252520-%25252003%25253A26%25253A1%3Cwbr%3E8%252520PM.png">
I'm just having a bit of trouble integrating something like 1/(x^4+2x^2+1). This kind of problem might not be on the test but I can't be sure. Help!
Edited by poke smot! (09/07/20 01:35 PM)
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Synthe
Gatorade me, bitch!


Registered: 11/10/12
Posts: 7,961
Loc: Three bags of Funyuns
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Re: Help bail me out! (of calculus) [Re: poke smot!] 3
#19255489 - 12/10/13 01:42 PM (10 years, 1 month ago) |
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Make a fetal position and remember to tuck in your head, hands, and legs in as you begin to fall.
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poke smot!
floccinocci floofinator



Registered: 01/08/03
Posts: 5,248
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Re: Help bail me out! (of calculus) *DELETED* [Re: Synthe]
#19255515 - 12/10/13 01:49 PM (10 years, 1 month ago) |
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Post deleted by poke smot!Reason for deletion: x
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deCypher



Registered: 02/10/08
Posts: 56,232
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Re: Help bail me out! (of calculus) [Re: poke smot!]
#19255559 - 12/10/13 02:00 PM (10 years, 1 month ago) |
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Partial fractions.
-------------------- We are all in the gutter, but some of us are looking at the stars.
 
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HappyHooligan
Tree hugger


Registered: 11/06/13
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Loc: America
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Re: Help bail me out! (of calculus) [Re: deCypher]
#19256676 - 12/10/13 05:59 PM (10 years, 1 month ago) |
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You must have been desperate to have decided to ask a bunch of stoners & druggies for help with calculus?? lol
-------------------- Do you trust the government? You may be suffering from Stockholm Syndrome.
 
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OliverJames
Potion Brewer


Registered: 02/28/12
Posts: 3,085
Last seen: 6 years, 3 months
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Quote:
HappyHooligan said: You must have been desperate to have decided to ask a bunch of stoners & druggies for help with calculus?? lol 
Speak for yourself man, there are plenty of very intelligent people on this forum that are "Druggies and stoners" and are still really interested in science and math. You in Calc 2? I haven't solved a problem like this in over a year, I'm taking linear algebra right now. I know there are two or three methods for revolving a solid, the shell and the disc. I'm currently taking care of some work right now but checkout khan academy, very helpful
https://www.khanacademy.org/math/calculus/solid_revolution_topic/solid_of_revolution/v/solid-of-revolution---part-2
If I'm still up in a couple hours and ya need help I'll be on, but I got an exam real early tomorrow morning that I'm cramming for right now haha
Good luck man
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HappyHooligan
Tree hugger


Registered: 11/06/13
Posts: 483
Loc: America
Last seen: 6 years, 9 months
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Re: Help bail me out! (of calculus) [Re: OliverJames]
#19256755 - 12/10/13 06:14 PM (10 years, 1 month ago) |
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Quote:
OliverJames said:
Quote:
HappyHooligan said: You must have been desperate to have decided to ask a bunch of stoners & druggies for help with calculus?? lol 
Speak for yourself man, there are plenty of very intelligent people on this forum that are "Druggies and stoners" and are still really interested in science and math.
It was a joke.
-------------------- Do you trust the government? You may be suffering from Stockholm Syndrome.
 
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Jvells
Unity



Registered: 11/05/09
Posts: 3,031
Loc: East coast
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i was so positive that i was going to scroll all the way down and read a bunch of bullshit and no answer, i was right
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mr sniffles
expert textpert


Registered: 06/03/13
Posts: 1,663
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Re: Help bail me out! (of calculus) [Re: OliverJames]
#19256792 - 12/10/13 06:21 PM (10 years, 1 month ago) |
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first you need to understand how the method works, it takes little cylindrical onion slices and finds the area of each slice, and adds them up using integration.
ok so now we have what we need to know, it helps if you draw out what you want to integrate and see if its with respect to x or y.
2*pi*r*h*dx is the area of one of those cylindrical slices
r=x since the radius along the x axis is x (rotated around y axis)
in this case, it would be y since its easier that way.
so integrate 2*pi*r*h*dx
r would be x, and h would be y but to integrate it properly you would need it in terms of x hence your function.
i took calculus two years ago so i don't really remember it that well. but you should be able to solve it using www.wolframalpha.com
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blackhawk
Newton's Law of Majesticity



Registered: 04/02/11
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Re: Help bail me out! (of calculus) [Re: mr sniffles]
#19256821 - 12/10/13 06:25 PM (10 years, 1 month ago) |
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Wait so what did you do?
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mr sniffles
expert textpert


Registered: 06/03/13
Posts: 1,663
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Re: Help bail me out! (of calculus) [Re: blackhawk]
#19256854 - 12/10/13 06:33 PM (10 years, 1 month ago) |
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2*pi*r = circumference h = height dx = distance between each slice
we multiply circumference and height, we get the area of revolution. then we integrate it with respect to x to fill out the area with the little dx slices.
im not a good teacher
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xbloodwhipx

Registered: 02/24/12
Posts: 12,791
Last seen: 4 years, 5 months
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Re: Help bail me out! (of calculus) [Re: mr sniffles]
#19256950 - 12/10/13 06:47 PM (10 years, 1 month ago) |
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Fuck it... im never going to college
Edited by xbloodwhipx (12/10/13 07:26 PM)
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Jvells
Unity



Registered: 11/05/09
Posts: 3,031
Loc: East coast
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Re: Help bail me out! (of calculus) [Re: xbloodwhipx]
#19256965 - 12/10/13 06:49 PM (10 years, 1 month ago) |
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Im in college and that post is making me want to switch out
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OliverJames
Potion Brewer


Registered: 02/28/12
Posts: 3,085
Last seen: 6 years, 3 months
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Quote:
HappyHooligan said:
Quote:
OliverJames said:
Quote:
HappyHooligan said: You must have been desperate to have decided to ask a bunch of stoners & druggies for help with calculus?? lol 
Speak for yourself man, there are plenty of very intelligent people on this forum that are "Druggies and stoners" and are still really interested in science and math.
It was a joke.
Sorry man, didn't mean to come off as an asshole. Just bugs me when people find out that I smoke and do drugs and instantly assume I'm not intelligent or hardworking because of it. Just a bad stereotype that seems to be constantly perpetuated by closed minded individuals
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HappyHooligan
Tree hugger


Registered: 11/06/13
Posts: 483
Loc: America
Last seen: 6 years, 9 months
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Re: Help bail me out! (of calculus) [Re: OliverJames]
#19257101 - 12/10/13 07:10 PM (10 years, 1 month ago) |
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Yeah, like I smoke weed everyday, but I'm a full time college student, work 30+ hours a week, looking for a second part time job, active in several volunteer groups at my school... but literally every time people tell me "Dude don't smoke, it will make you lazy"
-------------------- Do you trust the government? You may be suffering from Stockholm Syndrome.
 
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mr sniffles
expert textpert


Registered: 06/03/13
Posts: 1,663
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i don't understand how people do that. i used to smoke everyday but it just interfered with my memory and how i learned stuff.
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Mush4Brains
LOOL HACKED!!!

Registered: 07/31/13
Posts: 4,419
Last seen: 9 years, 2 months
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Re: Help bail me out! (of calculus) [Re: xbloodwhipx]
#19257188 - 12/10/13 07:23 PM (10 years, 1 month ago) |
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Quote:
xbloodwhipx said:

Fuck it... im never going to collage 
Or college, for that matter.
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Epigallo
Stranger
Registered: 09/17/06
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Re: Help bail me out! (of calculus) [Re: Mush4Brains]
#19257283 - 12/10/13 07:41 PM (10 years, 1 month ago) |
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Just integrate, find the average value of y, then pi R square that shit.
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blackhawk
Newton's Law of Majesticity



Registered: 04/02/11
Posts: 8,465
Loc: Where Jimmies are Rustled
Last seen: 18 hours, 43 minutes
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Re: Help bail me out! (of calculus) [Re: Mush4Brains]
#19257310 - 12/10/13 07:45 PM (10 years, 1 month ago) |
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I'm in calc 1 right now  Had 99 problems, but this ain't one
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DieCommie

Registered: 12/11/03
Posts: 29,258
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Re: Help bail me out! (of calculus) [Re: poke smot!]
#19257418 - 12/10/13 08:09 PM (10 years, 1 month ago) |
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Quote:
mr sniffles said: first you need to understand how the method works, it takes little cylindrical onion slices and finds the area of each slice, and adds them up using integration.
ok so now we have what we need to know, it helps if you draw out what you want to integrate and see if its with respect to x or y.
2*pi*r*h*dx is the area of one of those cylindrical slices
r=x since the radius along the x axis is x (rotated around y axis)
in this case, it would be y since its easier that way.
so integrate 2*pi*r*h*dx
r would be x, and h would be y but to integrate it properly you would need it in terms of x hence your function.
i took calculus two years ago so i don't really remember it that well. but you should be able to solve it using www.wolframalpha.com
Quote:
deCypher said: Partial fractions.
This looks like the way to do it to me too. First set it up as described, then use partial fraction decomposition. Note that what you are attempting to integrate is not correct. If you set it up correctly then the integral is easier.
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