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Proofs are the shit by Whitey Fillyleg - Fri, 12 Sep 2014 20:51:34 EST ID:TrfloaeP No.14361 Ignore Report Reply Quick Reply
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Sup guys. I'm a couple weeks into my first MATH class that is based around proofs and it turns out I'm fucking awesome at this type of thing. I had a very difficult time learning Cal2 and Cal3 because of poor quality of previous education, other factors, etc.

So, my question to you guys is, what do the people that are naturals when it comes to the formal proof methodology of thinking do? What kind of career should I be focused on, and what are other classes that are similar to this type of thing? I know it will depend on university wrt names of classes, but I have heard Modern Algebra is one of them and Real Analysis is another.

I'm also interested in "Set Theory", but do not know where to start or if/how it relates to proofs.. Thanks.
Fucking Badgestone - Sat, 13 Sep 2014 00:26:31 EST ID:Hs5ANTy/ No.14363 Ignore Report Quick Reply
I don't have the energy to rant to you about what constitutes good mathematics right now, but math is basically all about defining things and then proving things about them. If you really like this stuff, consider becoming a mathematician.
Molly Sacklestotch - Sat, 13 Sep 2014 19:01:40 EST ID:VWxuWxBu No.14365 Ignore Report Quick Reply
If you *really* like proofs (and want to learn about formal proofs), than you should take logic and set theory (although it is possible to like logic and not set theory)

Should I be a numerologist? by Eliza Fammerlere - Thu, 28 Aug 2014 00:14:38 EST ID:NE+OsI8C No.14331 Ignore Report Reply Quick Reply
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I look at math equations and I read aloud what pertains to the universe (1 and or/2 [in the future which is the past])

I just write out simple math equations


1+1 = life, 2=life with god, 2+2 = universal communication. and there are many more outcomes, simply one for each individual for those simple equations.

Its like I can peer into the soul of other people with math.

Lately, my math equation of my life = 2+2=5 (1 being innate, the universe) waiting for it to become 2+2=6. (when 1+1 (FOR HOW DOES ONE BECOME TWO WITHOUT BEING ONE ITSELF) becomes the new innate and we shift into the next predestination by means of a new god)

More info on 2+2=5 is I died, saw the universe, deemed everythings plural, thus attempting to recreate my lifes equation into 2+2=6.
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Hedda Piddlehodge - Mon, 01 Sep 2014 18:08:50 EST ID:7smvO3L9 No.14342 Ignore Report Quick Reply
okay, i follow you, but where do hypperreals fit in
Ebenezer Febberstod - Wed, 03 Sep 2014 00:20:31 EST ID:Dk8yywxc No.14346 Ignore Report Quick Reply

The hyperreals fill in the gaps between the meanings we can express and the ones we can't. Everything is continuous, but our finite minds can only approximate with the discrete. While we're in 2+2=4 our experiences will point outside of it, leading to the intuition that infinite small quantities exist wedged within the cracks of our existence. It is just as true but we cannot touch it without transcending to beyond 6, into an inaccessible singular quantum that cannot be even expressed in this frame. From the regular reals, we add all these quantums to get the hyperreals.

Essentially they're between the kinks. x-19y = 404z^2/9
Clara Gemblewill - Thu, 04 Sep 2014 01:57:37 EST ID:qt5i3eqa No.14348 Ignore Report Quick Reply
Are you Doctor? From /psy/? You are aren't you? Your schizophrenic ramblings are structured exactly like Doctor's were.
Lillian Crellerbutch - Fri, 05 Sep 2014 00:45:33 EST ID:gzRif05L No.14349 Ignore Report Quick Reply
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>Should I be a numerologist?

Sure. Be a numerologist.
But see a psychiatrist.

The delusions you're posting here seem pretty harmless, but you need to be monitored in case they turn into something that will cause you to harm yourself.
Henry Momblewetch - Wed, 10 Sep 2014 13:54:16 EST ID:8Zy6ydRZ No.14357 Ignore Report Quick Reply
ur doing it wrong though OP & making me cringe a bit

At least study the history of numerology, sacred geometry, & alchemy. Listen to some Manly P Hall history lectures.

see you on /spooky/

help, precalc final tomorrow by Alice Drizzletidging - Mon, 25 Aug 2014 22:37:15 EST ID:kQQi+WA1 No.14313 Ignore Report Reply Quick Reply
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One thing I want to work on is these box construction problems.
A box is being constructed by cutting 2 inch squares from the corners of a rectangular sheet of metal that is six inches longer than it is wide. If the box is to have a volume of 270 cubic inches, find the dimensions of the metal sheet.
L = W+6
H = 2
Does the volume, 270 = (w-4)(w+2)2 ???
How do i set this up? is that right? would appreciate as much help as you can give. Thanks!
6 posts and 1 images omitted. Click Reply to view.
Walter Gendlekan - Wed, 27 Aug 2014 01:34:52 EST ID:kTObtecm No.14324 Ignore Report Quick Reply
Skip trig if you want, but make sure you're a god at trig.
If you have a good calculus teacher, s/he'll make you practice trig inside and out.

It also depends on what you're wanting to do.
If you're a math or engineering major, then you'll want to formally introduce yourself to the basics by taking trig.
Ernest Decklefield - Wed, 27 Aug 2014 14:57:04 EST ID:kQQi+WA1 No.14327 Ignore Report Quick Reply
okay that's what i thought. thanks! nb
Isabella Lightcocke - Wed, 27 Aug 2014 15:55:43 EST ID:Gw2IN3ba No.14328 Ignore Report Quick Reply
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I never took trig nor precalc - in highschool or college. Hell, I just skipped my last two years of highschool. I took a placement test and was allowed to go straight into calculus. What little trig I needed to know for calculus was in an appendix at the back of my calculus book. I was taught the basics of trig in geometry anyway; and I taught myself the derivations of the identities I wasn't familiar with. IMO, devoting your time to an entire course in trig is a waste.
Nathaniel Pemmlestone - Wed, 27 Aug 2014 19:48:07 EST ID:BJycWA4m No.14330 Ignore Report Quick Reply
I fucking loved this problem back in precalc because I understood before anyone.

Those were the good days
Martha Clandleford - Thu, 28 Aug 2014 13:59:18 EST ID:kQQi+WA1 No.14333 Ignore Report Quick Reply
Aced the precalc final. was really pretty easy. yay!
anyway, i think i will be studying trig over the break with that girl, that way i can i can go straight to calculus!
Math rocks!!!

Math Placement Test Shit by Fanny Duckfuck - Tue, 26 Aug 2014 21:43:16 EST ID:NuE2NaRH No.14320 Ignore Report Reply Quick Reply
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I'll spare you the details and tell you my basic situation. I'm a 2nd year college student at a community college and in order to graduate in a timely manner I need to take Pre-Calculus. Problem is I don't have the math requirements to do it, so I need to re-take a placement test in order to get a good enough grade to take it.

I have a couple study guides with example questions and such so there's basic arithmetic (addition, decimals, fractions, etc.) and things like rational numbers, polynomials, quadratics, scientific notation, factoring (honestly I could probably scan the study guide if someone really wanted me to).

I was curious if anyone had any specific studying advice or really anything remotely useful because I'm freaking out about this because this shit is pretty goddamn important.
Ernest Decklefield - Tue, 26 Aug 2014 23:17:08 EST ID:kQQi+WA1 No.14321 Ignore Report Quick Reply
i took my placement test a few months ago. after six years w/o doing math i made it into precalc.
One thing I remember is you have to know a^2 + b^2 = C^2
do you remember Pythagorean theorem? look it up if you don't.
that's all i can remember.
that and know how to solve for x, know how to factor.
hope that helps a little bit
Ernest Decklefield - Tue, 26 Aug 2014 23:20:29 EST ID:kQQi+WA1 No.14322 Ignore Report Quick Reply
and yeah, if you can do everything on the study guide, you should be fine. I never got a study guide. i'm really tired though, so i might not know what i'm talking about.
I'm stressing about my precalc final. If I have 84 % in the class right now, and the test is worth 30%. what kind of grade do i need to get an A, or B?
Fuck! Horsepiss! Son of a two balled bitch!
Have you seen Snuff Box, OP?
Ernest Decklefield - Tue, 26 Aug 2014 23:38:43 EST ID:kQQi+WA1 No.14323 Ignore Report Quick Reply
But seriously, you should be able to talk a counselor into letting you take precalc
Fanny Duckfuck - Wed, 27 Aug 2014 07:26:41 EST ID:NuE2NaRH No.14325 Ignore Report Quick Reply
I already talked to them about taking precalc but basically they're not allowed to unless I have a kind of "math proficiency score" above a certain level.

And there isn't like a letter grade it's just like a score. I have no idea how it works but I know need to get like over a 31 or something.

Cute little abstract algebra thing by Ernest Gengerfield - Mon, 25 Aug 2014 00:34:32 EST ID:yGgK6aCs No.14307 Ignore Report Reply Quick Reply
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If you define an inverse operation as (in addition notation):
a + b = a + (-b), then the inverse operation is never commutative
(a - b does not equal b - a)
regardless of the status of the original operator unless both of those elements are identical.
I smoked nicotine, cannabis, drank coffee and went for a walk while listening to Terence Mckenna and this literally fell out of my head. Is this right? If you wrote the inverses of the inverse operation expressions, they're different unless the elements are identical, in which case it returns the identity element. You guys ever realize really specific shit like this while out and about?
Albert Fellerstock - Mon, 25 Aug 2014 05:46:37 EST ID:V9psgK+4 No.14309 Ignore Report Quick Reply
If you used the multiplicative notation, this result would appear far more intuitive.

a/b = b/a if and only if a = b.

I love getting those realizations out of the blue. It's even better when I'm intoxicated.
Alice Mussletere - Mon, 25 Aug 2014 09:02:33 EST ID:EvoUDt1O No.14310 Ignore Report Quick Reply
This is false. Consider that a/b=b/a is true as long as a^2=b^2. So if we let a=-1 and b=1 then our statement is true but a and b are not equal.

I'm sure you can think of more examples.

swarm theory by Betsy Trothood - Thu, 21 Aug 2014 06:36:18 EST ID:tzbijKoV No.14295 Ignore Report Reply Quick Reply
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posted on /chem/ as well but i know there are formulas for this. langtons ant being the one dimensional precursor.

does anyone have a clue as to where i can read actual numbers on this?

also, as always; discuss
Eugene Snodridge - Fri, 22 Aug 2014 20:16:12 EST ID:0P74hB5y No.14299 Ignore Report Quick Reply
idefk but damn that game of life....
Edwin Fonningdock - Sat, 23 Aug 2014 10:53:22 EST ID:orekpRAb No.14301 Ignore Report Quick Reply
Cellular automata is a basic implementation of swarm intelligence

It's more of a state-based computational thing than a numbers thing

I am fucked by James Huggleledge - Wed, 13 Aug 2014 17:08:21 EST ID:YNH/O7Fa No.14283 Ignore Report Reply Quick Reply
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So, I have a math placement exam coming up, and I am pretty sure I am fucked.
Though I did well in math during high school, it has been a few years since I graduated, and none of this is looking too familiar.
I am particularly having issues with finding domains. I have been trying to find practice problems similar to the ones I am working on now, but to no avail. I have an answer key to this practice test, but it doesn't explain shit. So, if someone could please explain domains in plain English, that would be great.

Here are some of the problems that appear on the practice test. I have simplified them, but I just don't understand at what point I am supposed to be finding the domain (before or after simplifying) and how to do that.


Basically, I feel like a fucking idiot, so if anyone could help, I would be eternally grateful.
4 posts and 1 images omitted. Click Reply to view.
Beatrice Darthood - Sun, 17 Aug 2014 01:08:34 EST ID:Dk8yywxc No.14290 Ignore Report Quick Reply

Do you know the difference between a filter and an ideal?

gb2 junior college peasant
Faggy Druckleshaw - Sun, 17 Aug 2014 19:16:39 EST ID:Y0JO63bd No.14291 Ignore Report Quick Reply
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nigga please i know about posets and subsets

that's a pretty irrelevant point though. it's reasonable to mock someone for not knowing how to change a tire - you don't yell at the person making fun of them "OH YEAH CAN YOU FIX A BROKEN HEAD GASKET BY YOURSELF HUR HUR HUR"

just because i may or may not know advanced mathematics, it doesnt affect my power to mock fools who dont know basic mathematics
Ernest Honeywell - Tue, 19 Aug 2014 20:39:23 EST ID:HLw3q9Du No.14292 Ignore Report Quick Reply
>it doesnt affect my power to mock fools who dont know basic mathematics
Why berate someone on a board about mathematics for understanding less math than you though? People come here for help. This isn't /b/. If you're coming here just to mock people who know less than you (and readily admit it), move the fuck along.
Doris Chuvingwutch - Tue, 19 Aug 2014 21:49:43 EST ID:Gw2IN3ba No.14293 Ignore Report Quick Reply
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So just to recap:

>I feel like a fucking idiot, so if anyone could help, I would be eternally grateful.

>holy fuck this nigga doesnt know a domain from a denominator? go back to jr high dog
Doctor Foster - Wed, 20 Aug 2014 05:23:39 EST ID:BfGCwHN9 No.14294 Ignore Report Quick Reply
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www.coolmath.com Maybe this will help? SMH www.math4kids.com

Free Academic Courses Online by Polly Blatherwater - Fri, 25 Jul 2014 03:21:10 EST ID:mSE/qEmh No.14247 Ignore Report Reply Quick Reply
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I know there are at least a couple websites that offer free courses, but the only one I can remember is edX.org, which offers more career-specific courses and I'm looking for general stuff. I just want to take math from the ground up, starting with elementary algebra. /math/ where can I learn algebra online?
Oliver Sodgekork - Fri, 25 Jul 2014 07:41:35 EST ID:Gw2IN3ba No.14248 Ignore Report Quick Reply
There really should be a sticky for this. It seems every other thread is asking for exactly what this site offers:

Charles Fudgefoot - Fri, 25 Jul 2014 17:56:08 EST ID:8PJ0nVdr No.14249 Ignore Report Quick Reply

For just math tutorials, Patrick is pretty good.
Edwin Ponninglutch - Sun, 27 Jul 2014 05:44:13 EST ID:mSE/qEmh No.14251 Ignore Report Quick Reply
Exactly what I was looking for thank you.
Molly Wapperham - Wed, 13 Aug 2014 20:12:48 EST ID:ptieClIw No.14286 Ignore Report Quick Reply
MIT's opencourseware is also great when you get to higher level maths and math related subjects:
Otherwise until you get to that point, khan academy.
Archie Worthingfield - Sun, 07 Sep 2014 19:10:56 EST ID:xvgqavvT No.14355 Ignore Report Quick Reply
From the list/guide here: http://www.staff.science.uu.nl/~Gadda001/goodtheorist/primarymathematics.html I used this course on beginner's algebra: http://www.wtamu.edu/academic/anns/mps/math/mathlab/beg_algebra/ and also a few beginner's algebra books I found used in local bookstores when I wanted to refresh highschool math.

I then did Sheldon Axler's Precalculus, because it assumes you remember no trig .

A mathematical and artistic exercise: Higher Dimensional Beings by Cedric Gollergold - Thu, 10 Jul 2014 01:30:30 EST ID:yGgK6aCs No.14192 Ignore Report Reply Quick Reply
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What I'm wondering is, what would it look like when a higher dimensional being moved through our dimensions? Obviously not a completely serious thread.
The artist/scientific portion of what I'm asking is: What would an intelligent life form look like in their n-dimensional glory?
The mathematical portion: I know you savages are capable of projecting n-dimensional structures into 3-dimensions. Has anything cool like this been done before? I'd be much more interested in projections with a time dimension.

The reason this interests me is that I'm fascinated with absolutely massive structures. The idea of a rapidly transforming organic structure popping in and out of existence is probably the most epic thing I can think of. The Halo games have been the most impressive things I've seen when it comes to showing you things with breathtaking scale. If the n-dimensional organic being was huge and a special effects company or game developer decided to take a swing at something like this, I'd be thrilled. I wouldn't mind you guys just talking about this instead of linking to media. I just don't hear this talked about very often.
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ASSHOLE JUNKIE - Wed, 06 Aug 2014 09:11:13 EST ID:otqnqn2l No.14269 Ignore Report Quick Reply
smoke DMT after reading flatterland

>your answer
Hannah Blorryville - Fri, 08 Aug 2014 15:31:05 EST ID:/dt3ybWI No.14273 Ignore Report Quick Reply
Very Related OP: https://www.youtube.com/watch?v=N0WjV6MmCyM
Nell Drinningfuck - Sun, 10 Aug 2014 18:01:14 EST ID:uspvjvJI No.14277 Ignore Report Quick Reply
>This video is not available in your country.

Did I just get teleported to China? WTF?
Nicholas Grimgold - Mon, 11 Aug 2014 19:45:31 EST ID:yGgK6aCs No.14278 Ignore Report Quick Reply
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That's exactly where I got the idea, actually. I was just wondering if you guys could get crazy on me. As a physics student, we regard you math guys as people who just do wild shit for no reason that nobody ever asks for. We pretty much assume that you could answer most questions we have but as I've framed my questions as more open, I don't expect too much. I will certainly be reading flat land and flatter land and hopefully smoke DMT at some point in the process. Right now both of my threads are the top threads. This is a terribly slow board isn't it, you hard working motherfuckers?
Hugh Brarringville - Wed, 13 Aug 2014 13:50:05 EST ID:Hs5ANTy/ No.14282 Ignore Report Quick Reply
I'm just repeating myself here, but read Diaspora. Flatland and its sequels are good but if you already have some math background they'll all cover some pretty obvious stuff.

There are tons of ways for life to exist in a world with three spacial dimensions, and even more in four or more, assuming physical laws which work in those spaces. Do you have any more specific questions or do you just want to be entertained?

If people in a four dinensional world had cars, their wheels could have two degrees of freedom and still be 'flat' on one side. Their roads would approxomate three dimensional tubes kr parallelpipeds and the wheels would touch the road as a flat 2d shape instead of a line. There would be no left or right side of the road, but the road would probably still just connect two points in something approximating a thin line as they do in our world. I could go on and on but after a point it's really pretty boring.

Quick nit picky thing about Epsilon Delta Limits by Betsy Secklehid - Fri, 08 Aug 2014 08:51:33 EST ID:yGgK6aCs No.14271 Ignore Report Reply Quick Reply
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I notice a few sources I've looked at specify that |x-a| is greater than 0, but never bother to do the same thing with |f(x)-L|. In my mind, if they do it with one and not the other, then I'm going to assume there is a reason for doing so and spend all sorts of time thinking about why the definition isn't symmetrical in this way. However, in my opinion specifying that the absolution value of anything is greater than zero seems completely redundant if we're beyond the discussion of what an absolute value is, so it seems to me that saying |x-a|< epsilon is complete. Is there a reason for specifying |x-a| is greater than zero or is this just a habit that's perpetuated?
3 posts omitted. Click Reply to view.
Fanny Lightham - Sun, 10 Aug 2014 05:55:19 EST ID:qz3c7Bt+ No.14276 Ignore Report Quick Reply
You need |x-c| > 0 so that {x | |x-c| < delta} is a neighborhood. Whenever you show continuity of f at point c, you're demonstrating for a neighborhood V containing c, you'll get a neighborhood f(V) containing f(c).
Fucking Gebberlock - Tue, 12 Aug 2014 17:31:37 EST ID:5HpdLBMD No.14280 Ignore Report Quick Reply
Because then |f(x)-a| could equal zero. This can cause problems with definitions.
Eliza Dissleway - Tue, 12 Aug 2014 20:48:44 EST ID:Gw2IN3ba No.14281 Ignore Report Quick Reply
This. It seems so obvious now you mentioned it.

Disregard my previous answer OP; apparently I didn't have my thinking cap on when I replied.
driven !FTPgBqDDy. - Wed, 13 Aug 2014 21:57:16 EST ID:y5R4M4OS No.14287 Ignore Report Quick Reply
That's because there's a difference between the definitions for the limit of a sequence and the limit of a function. I don't have my analysis textbook but in a couple of days I can expand on this

Also the first thing inside your absolute value sign should be something that changes with respect to something else (e.g. xn) because it doesn't make sense to be continually comparing fixed quantities. So i'll use xn to represent a sequence x1, x2, x3, ...

|xn-a| can be zero, it's just not very interesting and doesn't occur for things like xn = 1/n (a is a fixed quantity so it can't cancel with 1/n).
Ernest Gengerfield - Mon, 25 Aug 2014 00:44:52 EST ID:yGgK6aCs No.14308 Ignore Report Quick Reply
1408941892614.jpg -(34803B / 33.99KB, 496x402) Thumbnail displayed, click image for full size.

I totally get it now. We want to know the behavior around some point, disregarding what's actually happening at that point. However, we're perfectly fine with |f(x)-L| being zero. That's exactly where the asymmetry comes in. Thanks! No bump.

That background by Basil Ponderseg - Tue, 05 Aug 2014 17:26:04 EST ID:y0c2N06s No.14265 Ignore Report Reply Quick Reply
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How does one make an animation like here in the background?
Ebenezer Peggleman - Tue, 05 Aug 2014 20:48:19 EST ID:sPd/0oB/ No.14267 Ignore Report Quick Reply
I'm the guy who advised you to post on /math/.
You need to learn how to code to at least make the gif/jpg/png.

Learn a simple language on which you can draw stuff, like Processing. Draw simple stuff first (bouncing ball), then move on more complicated pictures, like the Mandelbrot set or 2D Perlin Noise.
Draw a square grid, then draw an hexagonal grid, then draw rainbows all over it, then change the coordinates to polar to get a spiral.

Rebecca Blythehood - Tue, 05 Aug 2014 22:36:57 EST ID:4glIJRAX No.14268 Ignore Report Quick Reply
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Are BP oil spill jokes still relevant?

cone surface area question by Molly Blackman - Thu, 31 Jul 2014 06:31:54 EST ID:Yu7owZ2i No.14254 Ignore Report Reply Quick Reply
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a water tank has the shape of a cone. the tank is 10 meters high and has a radius of 3 meters at the top. if the water is 5 meters deep ( in the middle), what is the area of the top of the water?

thanks guise

pic unrelated
Archie Blickleshit - Thu, 31 Jul 2014 18:56:53 EST ID:atHzm3qN No.14255 Ignore Report Quick Reply
Oh, c'mon. You're not even trying.

A = π3 (3+10*2+3*2)

If you only care about the surface area of the top ( a circle) you would just take the square of r (= 3) and multiply it by pi.
Angus Ferrywell - Fri, 01 Aug 2014 03:08:22 EST ID:Yu7owZ2i No.14257 Ignore Report Quick Reply
but the radius given is the maximum radius at the top, how do you calculate the radius of the top circle formed by the water when its 5 meters deep?
Ian Sagglewick - Fri, 01 Aug 2014 11:37:04 EST ID:5quJ2CR5 No.14260 Ignore Report Quick Reply
Its a cone, you know the radius at the top and bottom and the height. Its just lines bro.
Jack Sizzlewodge - Sun, 03 Aug 2014 13:36:02 EST ID:8NZnQ0yA No.14262 Ignore Report Quick Reply
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Solve for the radius of the circle of the top of the water using similar triangles:

Solve for the area of the top of the water using the radius:
Fucking Bardridge - Mon, 04 Aug 2014 21:03:34 EST ID:uspvjvJI No.14263 Ignore Report Quick Reply
Just think about the geometry of it in your head. The radius at the top of the cone is 3, and the radius at the bottom is 0 because it's just a point. The radius increases from 0 to 3 proportionally with the height increasing from 0 to 10, so if the water height is half of the maximum, then the radius is also half of the maximum.

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