Tests

A lot of tests coming up, including a bunch of Finals Tests. But Not To Worry

Q1: 94%
Q2: 95%
Q3: 94%
Q4: ??%
My school has quarterlies, midterms, regents, crap like that. I remember getting 100 on my third quarterly.

15,000 posts

I've been around for about 1,000 of them.

At 5/29/07 02:35 PM, BlackmarketKraig wrote: ..::Pathetic AIM Hacker::..

Holy Shit I DID IT!

nahhh ;) I'm not that stupid.

At 5/29/07 09:22 AM, dELtaluca wrote: dont want this lost :'(

At 5/29/07 07:41 AM, dELtaluca wrote: a little maths test for people :P

1. (Not sure, perhaps one of the further modules)

find and classify all stationary points of the function

f(x,y)=x^2 - 4xy + y^3 + 4y

Uh.. I haven't done 3 dimensional equations yet so I'm going to guess a little here.

f'(x,y) in terms of x: 2x-4y
in terms of y: -4x+3y^2+4

both should = 0 for stationary points

2x=4y
x=2y

-4(2y)+3y^2+4 = 0
3y^2-8y+4 = 0
y = 2/3, 2

x = 2y SO....

(4/3, 2/3, z) and (4, 2, z) are the critical points (stationary).
solving for z is easy I don't feel like doing so right now

2. (Core 4)

integrate with respect to x;

1/sqrt(e^(2x) - 1), for x>=0

Ok.
That's hard but:

1/sqrt(e^2x-1)
e^2x/e^2x*1/sqrt(e^2x-1)
1/e^2x*2e^2x/(2e^2x*sqrt(e^2x-1))
1/(1+e^2x-1)*2e^2x/(2e^2x*sqrt(e^2x-1))
1/(1+sqrt(e^2x-1)^2)*2e^2x/(2e^2x*sqrt(e^2x-1 ))
u = sqrt(e^2x-1)
du = 2e^2x/(2e^2x*sqrt(e^2x-1))

1/(1+u^2) -> tan-1(u) -> tan-1(sqrt(e^2x-1))

Ok, so I worked backwards after finding the solution on the calculator. But seriously, how the hell would anyone figure out to do that on their own?

3. (c4 Jan07) This was a question on my c4 paper in january

a curve is defined implicitly by the equation
x^2 + xy + y^2 = 3

show that the curve has two stationary points, and find their coordinates

2x+x(dy/dx)+y+2y(dy/dx)=0
dy/dx = 0
2x = 0
x = 0

0 + 0 + y^2 = 3
y = +-sqrt(3)

(0, sqrt(3)) and (0, -sqrt(3))
EASY!

(the above question that i made up) (C4)

find the general solution to the differential equation

dy/dx = (xsin x)/(cos^2 y)

have fun :P ill post answers when/if a few people attempt to answer, and ill say if someone gets it right obviously

cos^2 y dy = xsinx dx

sin(2y)/4+y/2 = sinx-xcosx+C

Done :P

Oh BTW I have chickenpox

At 5/29/07 03:39 PM, Glaiel-Gamer wrote:

At 5/29/07 09:22 AM, dELtaluca wrote: 1. (Not sure, perhaps one of the further modules)

f'(x,y) in terms of x: 2x-4y
in terms of y: -4x+3y^2+4

if by 'f'(x,y) in terms of X' you mean, partial derivitave of f with respect to 'X' then ill agree :P get your terminology correct please.

(4/3, 2/3, z) and (4, 2, z) are the critical points (stationary).

there is no 'z' so ill ignore your next comment, but the stationary points are correct yes.

ANSWER + 'correct' method

using 'p' for the partial derivitive symbol:

pf/px = 2x - 4y, pf/py = -4x + 3y^2 + 4, rearrange pf/px to give x = 2y, substitute into pf/py
3y^2 - 8y + 4 = 0
(3y - 2)(y- 2) = 0, y = 2/3, 2 (use pf/px ->)

stationary points: (4/3,2/3) (4,2)

p^2f/px^2 = 2, p^2f/py^2 = 6y, p^2f/pxpy = p^2f/pypx = -4, forming the hessian matrix:
H =
| 2 , -4 |
| -4 , 6y |

with determinant |H| = 12y - 16, neither stationary points are degenerate, continue to classify

| H - hI | =
|2 - h , -4 |
| -4, 6y- h| = (2-h)(6y-h)-16

for y = 2, we have:

h^2- 14h +8 = 0
(h-7)^2 = 41
h = 7 pm sqrt{41}, both values of h are positive: therefore point (4,2) is a local minimum

for y = 2/3 we have:

h^2 - 6y - 6 = 0
(h-3)^2 = 15
h = 3 pm sqrt{15}, one negative, one positive: therefore point(4/3,2/3) is a saddle point

2.

tan-1(sqrt(e^2x-1))

ok, not the answer i had in mind, but a quick test (comparison to my own answer by trying values of x) they are equivalent functions, although i'd have no idea about how to convert one to the other, so ill give you half marks for using a calculator :P

Ok, so I worked backwards after finding the solution on the calculator. But seriously, how the hell would anyone figure out to do that on their own?

like this:

first substitution:
e^x = u, dx/du = 1/u

int 1/sqrt(e^{2x}-1}) dx = int 1/sqrt(u^2 - 1)*1/u du

second substitution:
u = secv, du/dv = secvtanv

int 1/sqrt(u^-1)*1/u du = int 1/tanv*1/secv*tanvsecv dv = int 1 dv = v + k

int 1/sqrt(u^2 - 1)*1/u du = sec^{-1}v + k

int 1/sqrt(e^{2x} - 1) dx = sec^{-1}(e^x) + k

like that ;)

3.

2x+x(dy/dx)+y+2y(dy/dx)=0

correct (...wait for it)

(0, sqrt(3)) and (0, -sqrt(3))
EASY!

completely wrong

2x+x(dy/dx)+y+2y(dy/dx)=0, dy/dx = (-2x - y)/(x + 2y) <=> x + 2y =/= 0

let dy/dx = 0, 2x + y = 0: substitute into original equation: y = -2x

x^2 - 2x^2 + 4x^2 = 3
3x^2 = 3, x = pm 1, y = mp -2

both stationary points satisfy x + 2y =/= 0: stationary points are:

(1, -2) (-1, 2)

4.

sin(2y)/4+y/2 = sinx-xcosx+C

correct, although it would've been nicer if you had actually shown your working out for the two integrals:

At 5/29/07 01:33 AM, Buzzwerd wrote:

2. Homosexuality

Homosexuals are flamboyant and do silly stuff, they're basically making fun of themselve

Do you actually think every gay person does that?
Some of you guys need to be enlightened...

At 5/29/07 04:23 PM, dELtaluca wrote: correct, although it would've been nicer if you had actually shown your working out for the two integrals:

Meh we've done them in class before so our teacher just let us treat that like a rule

Jokes

At 5/29/07 12:53 AM, BoMToons wrote:

1. AIDS

Lulz, U haf AIDZ!

2. Homosexuality

You're a FAG-GOT!

3. Religion

Hey guys, lets draw Mohammad with a bomb for a hat.

4. Abortion

Push the button for Jesus.

5. Terrorism

How many planes do you need?

6. Natural Disasters

Let's all build our houses on the fucking coast!

7. Disabilities

TIMMAY!

8. Mental Handicaps

Meh.

9. Child Abuse

"If your child isn't huddled over in a corner when you come home, you aren't being a good enough parent."

10. Rape

It's surprise sex, lulz.

11. Sex

Too much to choose.

12. Drugs

Pot smoking... whatever....

13. Alcohol

Luis is an alcoholic.

14. War

Bomb Iraq.

15. Race

Luis is a spic, I'm a cracker, we need a chink and a nigra. Shoop da woop?

16. Suicide

</wrists>

17. Emotional Disorders

You emo pussy.

18. Pregnancy

Go get knock up you fucking cum dumpster.

19. Gender (ie: women>men or vice versa)

Want to hear a joke... Women's Rights.

20. Immigration

Why doesn't Mexico have a good olympic team? Anyone who can run, swim, or jump gets across the border.

Honestly, I think they're all fair game, it's just that some of us choose to initiate them more than others. We also have favorites here on NG, seeming like the AIDS, emos, and dr0kn being our favorites.

God I took so fucking long to respond to this.

Screen Size

Nobody answered me question before, I'm making a video in flash (more freedom of editing and I know it best) and I'm wondering what should the screen size be? It will be played on a television.

Maths

At 5/29/07 08:05 AM, shazwoogle wrote:

=(e^(2x)-1)^-(1/2)
dx = 1/2(1/2e^2x)-x)^(1/2)

At 5/29/07 03:39 PM, Glaiel-Gamer wrote:

1/(1+sqrt(e^2x-1)^2)*2e^2x/(2e^2x*sqrt(e^2x-1 ))

At 5/29/07 09:22 AM, dELtaluca wrote:

p^2f/px^2 = 2, p^2f/py^2 = 6y, p^2f/pxpy = p^2f/pypx

What the hell are you guys on about? Seriously, take a day off, lads.

NG Rumble
Because my mod team counterparts are bashful and not full of themselves, I wanted to express my warmest applause to their newest title. I think the art and programming are brilliant, especially the AI.

http://www.newgrounds.com/portal/view/381115

At 5/29/07 05:23 PM, Kirk-Cocaine wrote: What the hell are you guys on about? Seriously, take a day off, lads.

well you see, you have will's failed attempt, glaiel's massively over complicated backwards method, and what you quite from my is just some secondorder partial dervitives. :P

At 5/29/07 05:25 PM, jmtb02 wrote: NG Rumble
Because my mod team counterparts are bashful and not full of themselves, I wanted to express my warmest applause to their newest title. I think the art and programming are brilliant, especially the AI.

http://www.newgrounds.com/portal/view/381115

Sweet game. I just owned Samurai Asshole. I fifened it.

Must have taken ages to make, the AI is incredible.

Re:NG Rumble

At 5/29/07 05:37 PM, BlackmarketKraig wrote: Must have taken ages to make, the AI is incredible.

Incredible? Christ. Nah im just pulling ya leg. It was alright but i wont bother saying that was rubbish or wicked yet. Will take it in to colly tomorrw and play 2 player, or 4 if thats possible. Kewel so far, P bot runs like a comical-fat man.

At 5/29/07 05:25 PM, jmtb02 wrote: NG Rumble
Because my mod team counterparts are bashful and not full of themselves, I wanted to express my warmest applause to their newest title. I think the art and programming are brilliant, especially the AI.

http://www.newgrounds.com/portal/view/381115

The game is really good, and the upgrades are ok, but with Alien Hominid I would have liked to shoot more freely...

Again, screen size!

So what do you guys think about the screen size? I will be playing the flash movie on a tv, but it won't all be totally animated (to save time). What stage/screen size should I use?

Size matters

At 5/29/07 06:01 PM, pixelz wrote: So what do you guys think about the screen size? I will be playing the flash movie on a tv, but it won't all be totally animated (to save time). What stage/screen size should I use?

somehtign that has the same screen ratio as tv, so 4:3 or 16:9.. or even 1.78:1

want to explain why u need ot know.. makign some adult films for us?

Re:Screen size

At 5/29/07 06:01 PM, pixelz wrote: Again, screen size!

So what do you guys think about the screen size? I will be playing the flash movie on a tv, but it won't all be totally animated (to save time). What stage/screen size should I use?

Here you go, check this out -

http://en.wikipedia.org/wiki/Aspect_ratio_%28 image%29

Basically depending on what telly you want it to play on, have it match either of those aspect ratios. I dont know much about aspect ratios but I should do, if it was me id import that picture, then stretch it up and match it to the canvas. Oh well anyway, have a read and see what you think.

At 5/29/07 06:06 PM, Lord-Sonx wrote: Size matters

At 5/29/07 06:01 PM, pixelz wrote: So what do you guys think about the screen size? I will be playing the flash movie on a tv, but it won't all be totally animated (to save time). What stage/screen size should I use?

somehtign that has the same screen ratio as tv, so 4:3 or 16:9.. or even 1.78:1

want to explain why u need ot know.. makign some adult films for us?

No, sorry guys no adult films with random flash added in... at least not for now. Its for school, I need to make a video on pollution probe, and me and this girl filmed it originally but the video got all messed and ruined, then she had to go so we quickly recorded the script. Now I'm stuck having to make the entire video. It has to promote pollution probe to youth and talk about what pollution probe is. I was thinking a good stage size would be like 720 by 480 or something, I heard some numbers like that somewhere. This ratio and proportion stuff, looks like math to me...

At 5/29/07 06:10 PM, pixelz wrote: me and this girl filmed it originally but the video got all messed and ruined

thats disgusting....

720 by 480 or something, I heard some numbers like that somewhere. This ratio and proportion stuff, looks like math to me...

well 4:3.. X100
400x300
or any two numebrs that share this ratio..
800x600 will do fine.

At 5/29/07 06:10 PM, pixelz wrote: I was thinking a good stage size would be like 720 by 480 or something, I heard some numbers like that somewhere.

A standard DVD has a width of 720 pixels. After that, it's just a matter of the aspect ratio you're going for. For example, a 4:3 would be 720x540, or a 3:2 would be 720x480.

At 5/29/07 05:25 PM, jmtb02 wrote: NG Rumble
Because my mod team counterparts are bashful and not full of themselves, I wanted to express my warmest applause to their newest title. I think the art and programming are brilliant, especially the AI.

http://www.newgrounds.com/portal/view/381115

NG RUMBLE

I know that game is SWEET i love it i'm hearing daily 1st! its AWSOME!!

At 5/29/07 06:14 PM, Lord-Sonx wrote:

At 5/29/07 06:10 PM, pixelz wrote: me and this girl filmed it originally but the video got all messed and ruined

thats disgusting....

She is disgusting, she is white but has squinty eyes all the time and is fat, like all round and greasy... and kidna reatarded too, the teacher would only let groups of 2 and I was by myself (intentionally, this is a civics class so everyone takes it, theres no acedemic but I got stuck with all the retards and the random gifties) and she was ina group of 3 but then the teacher asked me if it was ok for her to join, and I've never been mean to her and she seems to like me (as a friend, don't be getting any ideas) and I couldn't say no because they were all staring at me, the teacher, her, the other two girls (one of which is HOT). So I had to say "Fuck! Fine, but when this project is done, you will all suffer...." I wanted to say that...

720 by 480 or something, I heard some numbers like that somewhere. This ratio and proportion stuff, looks like math to me...

well 4:3.. X100
400x300
or any two numebrs that share this ratio..
800x600 will do fine.

800x600 eh? Sounds good, I'll give it a go!

Wow, I just noticed Adam Phillips 3 Brackenwood like flashes have the exact same score(4.24).

Weird

Re: Newgrounds Rumble
An awesome game.
I love it.

Theres so much unlockable content, options to change, great art, awesome stages.
It's just epic.
It would be better if the camera problems were fixed, but oh WAIT, theres an option to turn it off!

I really like this game, online multiplayer would be incredible...

nobody cares about my chickenpox :(

At 5/29/07 07:21 PM, pixelz wrote: 800x600 eh? Sounds good, I'll give it a go!

It seems to me that I once read that the numbers must be multiples of 16 (that may be completely false), but in that case a "4:3" DVD specific ratio should be 720x544.

At 5/29/07 08:57 PM, Glaiel-Gamer wrote: nobody cares about my chickenpox :(

THAT's what I forgot!
Be strong baby!

Thanks for the comments in here too!
I feel the NG luff.

Newgrounds Rumble
As someone pointed out, it has superb graphics, but the game play Fails in comparison to any SSB game.

My rating; 8.5/10 for graphics Gameplay-6/10

But overall that last lvl with convict is a bitch, and i loved it.

Favorate NG game thus far

At 5/29/07 08:57 PM, Glaiel-Gamer wrote: nobody cares about my chickenpox :(

Dude, you're 16, and I assume you go to public school. How did you not have them yet.

Go take an oatmeal bath. Cereally.