math problem...

[One_Bad_400]

can someone smart work this problem for me and give me the answer:ermm: :D

-3y< 2(3y+9)

[TRX_450]

im not real sure we aint done stuff like that alot but im guessin
3y is less than equal to 18

[One_Bad_400]

no... its got to get down to y< a number

[wilkin250r]

The domain is all real numbers between negative and positive infinity.

The range of the function is all real numbers greater than or equal to negative two.

[One_Bad_400]

i think it might be y is less then or equal to 8

[trict_out]

Originally posted by wilkin250r
The domain is all real numbers between negative and positive infinity.

The range of the function is all real numbers greater than or equal to negative two.

lol u gotta love this guy

[trick450r]

Originally posted by wilkin250r
The domain is all real numbers between negative and positive infinity.

The range of the function is all real numbers greater than or equal to negative two.

thats what i got

domain = reals
range = Y>_-2

[MXRACER86]

jezzzzz! Everbody knows that it equals "lift versus rotation"!:rolleyes:

[cjj]

Originally posted by One_Bad_400
can someone smart work this problem for me and give me the answer:ermm: :D

-3y< 2(3y+9)

-3y< 6y+18
-6y -6y
-9y< 18
__ __
-9 -9

-y< -2

or

y > - 2

I belive if the variable is a negative u switch the inequality.

[Quad18star]

Could it be 2 < /_ y ?? Sorry I don't know how to put the < over the _ . LOL

[trx400exxracer]

got to www.sparknotes.com they got all the amsweres to all of your subjects

[One_Bad_400]

holy poo... i was way off:confused: i hate this crap.. and i have a test tomorrow....

[Quad18star]

Originally posted by One_Bad_400
holy poo... i was way off:confused: i hate this crap.. and i have a test tomorrow....

I'll tell you how I did it , if you tell me how to do the < over the _ thing . LOL :p

[cjj]

Im almost positive it is y>-2

I should remeber we learned it a few weeks ago. :rolleyes:

[One_Bad_400]

HA!!! ok... i went there... but whats this stuff called?!?! lol...

[wilkin250r]

Originally posted by Quad18star
I'll tell you how I did it , if you tell me how to do the < over the _ thing . LOL :p

Use the underline function... :rolleyes: <




:blah: :macho

[Quad18star]

Originally posted by One_Bad_400
HA!!! ok... i went there... but whats this stuff called?!?! lol...

It's called MATH !!! . :blah:

[cjj]

inequalities i belive.

[One_Bad_400]

Originally posted by Quad18star
I'll tell you how I did it , if you tell me how to do the < over the _ thing . LOL :p


you go up to on your font stuff where it says B(bold) I(italics) U(underline) click underline and then put the < in there and it does it...

[rmz250]

haha I had a teston this stuff today. I don't even want the test back.

[wilkin250r]

Originally posted by cjj
Im almost positive it is y>2

Almost. It's negative two, not positive two.

[Quad18star]

Originally posted by wilkin250r
Use the underline function... :rolleyes: <

:blah: :macho

D'Ohhhh !!!!

And I thought it was some magic button on the keyboard that I've never seen before .

<

[cjj]

jeez what are u guys talking about this stuff is easy. I got like a 96 on it.

[cjj]

Originally posted by wilkin250r
Almost. It's negative two, not positive two.

woops i had that but didnt remebr if i had to switch that to.

[One_Bad_400]

i know... i'v never failed a test or missed a h/w assignment untill this stuff came up... lol

[Quad18star]

Originally posted by cjj
jeez what are u guys talking about this stuff is easy. I got like a 96 on it.

Ya it's easy once you grasp the concept of it .

You know what I hate .... Statistics !!!! I failed that damn course in college . The only thing I understood out of the whole course was that I failed by 2% .:grr:

[One_Bad_400]

HAHA!! well i'm still in high school... lol...

[wilkin250r]

Originally posted by Quad18star
Ya it's easy once you grasp the concept of it .

You know what I hate .... Statistics !!!! I failed that damn course in college . The only thing I understood out of the whole course was that I failed by 2% .:grr:

HAHAHAHA. That's funny.

[Quad18star]

Originally posted by One_Bad_400
HAHA!! well i'm still in high school... lol...

Post up more problems ... I want to see what I still remember and what I've forgotten over the years !!!!

[One_Bad_400]

ok... lol... ya'll can do my h/w for me... LMFAO!

-12> -2(4x+2)



-24>4(p-2)



1/3(x-9)< 18



1/2(8x+24)>4

[wilkin250r]

Greg, you can't possibly be challenged by simple algebraic inequalities.

If you REALLY want a challenge, walk me through Integration by Parts... :blah:

[One_Bad_400]

let me ask a question.............. WHEN AND WHERE IN THE HELL ARE WE GOING TO USE THIS AFTER I GET OUT OF SCHOOL!! :mad:

[JDiablo]

5(-3x - 2) - (x - 3) = -4(4x + 5) + 13

[One_Bad_400]

my questions first :D

[JDiablo]

Originally posted by One_Bad_400
let me ask a question.............. WHEN AND WHERE IN THE HELL ARE WE GOING TO USE THIS AFTER I GET OUT OF SCHOOL!! :mad:


Ye exactly we are graphing linear equations now and i really dont know why we need this stupid chit,find which point intersects with the y and x axis,and i hate it,takes up one whole piece of paper for a problem and the answer is like x=1;y=5

[Quad18star]

Originally posted by wilkin250r
Greg, you can't possibly be challenged by simple algebraic inequalities.

If you REALLY want a challenge, walk me through Integration by Parts... :blah:

If I'm walking you through something , you better keep your hands in your own pockets .

But all jokes aside ... the problem I had with math in college wasn't really the numbers but mostly the wording and different terms . For 13 years I went to french school ... after highschool I switched over to an english college . Going from understanding the french terms to english was like night and day . It confuzed the chit out of me ... reason I had very low marks . But I guess I should have expected that going into Engineering . LOL

[JDiablo]

anyway your answer is -2

[Quad18star]

Originally posted by One_Bad_400
let me ask a question.............. WHEN AND WHERE IN THE HELL ARE WE GOING TO USE THIS AFTER I GET OUT OF SCHOOL!! :mad:

If you go into any type of Engineering field , these become everyday things . Although they aren't usually as simple as this, you will find them .

If you're trying to find a perfect mixutre , trying to find loads , etc.

[wilkin250r]

Well, if you just want to be an idiot pushing a button in a factory making $7.50/hr for the rest of your life, then you won't need it.

However, if you plan to go to college and get a degree, then you DO need this stuff.

Here is one simple example. I don't use this stuff on the job, but I DO need this stuff to learn about my field. I need mathematical equations to describe, predict, and analyze magnetic fields.

I need simultaneous equations to analyze electrical circuit.

I don't need this stuff while I'm ON my job, but I need this stuff just to LEARN about my job. Mathematics is the language used to describe what I do.

[trick450r]

thats stuff is basic dood, i finished that section like 3 weeks ago with a 48/50 on the final test thingy...its the chemistry that keeps kickin my assi understand ballancing equations and writing equations....but empirial units and things like that make my brain feel like its sorrounded in paint thinner and its desintegrating....

[eastPAex]

Theres a book series called Shamms outlines that is good, they have them for chem to. i use them all the time it really helps if you give it an honest effort.

[wilkin250r]

Chemistry turned my brains into mush, too, but it wasn't the classwork. It was all the other idiots taking the class that didn't understand basic math. Friggen drove me insane to hear the instructor repeat himself over and over, and people STILL didn't get it.

I wasn't sure if I wanted to kill myself, or kill them.

[m_townsgreatest]

the original problem this started with is a breeze for me and im in 8th grade

[Bush0102]

how about this one? straight off a test i took today

using the first and second derivatives, find the local maxima and local minima of the following function:

y(x)=xˆ3 + 2xˆ2 - x + 1

ok, well first i had to find the first derivative and find its zeroes.

y'(x)= 3 xˆ2 + 4 x - 1

now, to find the zeroes

( - b +- √ bˆ2 - 4ac) / 2a

(- 4 +- 2) / 6

-1, -1/3

now, to find the second derivative

y''(x)=6x+4

plug the zeroes from the first derivative into the equation from the second

y''(-1)=-2 y''(-1/3)= 2

-1 is local maximum, -1/3 is local minimum

[Bush0102]

wow those characters didnt come out right, i'll try to fix them

hey i definetly go the answer...
3y<_ i'll just put < for my easiness

-3y<2(3y+9)
-3y<6y+18
__ ___ ___ divide each side by -3
-3 -3 -3

y<-2y-6
+2y
+2y

3y<-6
__ __ divide by 3
3 3

y< -2

thats the correct answer and im postive of it...learned this chit last year and i Aced every test.


oh and ur welcome:macho

Originally posted by wilkin250r
Chemistry turned my brains into mush, too, but it wasn't the classwork. It was all the other idiots taking the class that didn't understand basic math. Friggen drove me insane to hear the instructor repeat himself over and over, and people STILL didn't get it.

I wasn't sure if I wanted to kill myself, or kill them.

WOW!!!!
same with me!!!!
some girls in my class are extremely extremely dumb...im in advanced geometry and adcanved chemistry and the math we do in chemistry is the algebra we learned last year that i Aced...dude how are these girls so dumb and cant remember what 2x<6...lol those girls are sooo dumb they're like its 4 right? shes like no and goes into a huge speach...what a waste of my time

[400exrules]

i got y< -2


buuut, when you divide by a negative dont you flip the sign in an inequality?

so it might be y>-2

[JDiablo]

Originally posted by 400exrules
i got y< -2


buuut, when you divide by a negative dont you flip the sign in an inequality?

so it might be y>-2


Yup

[Plante400]

-3y < 2(3y+9)

-3y < 6y+18 <----------foiled

-6y from both sides

-9y<18

-9y/-9 < 18/9

y < -2

[Plante400]

Originally posted by quad&dirtbike
hey i definetly go the answer...
3y<_ i'll just put < for my easiness

-3y<2(3y+9)
-3y<6y+18
__ ___ ___ divide each side by -3
-3 -3 -3

y<-2y-6
+2y
+2y

3y<-6
__ __ divide by 3
3 3

y< -2

thats the correct answer and im postive of it...learned this chit last year and i Aced every test.


oh and ur welcome:macho


U do it the Long Way Homy

[watts16]

ya same hear im taking advanced chem and physics right now. some of the people in the classes should be in sophmore science. i just want to punch some of the people in there:o

[reichart90]

i never thought id use any of that crap. i hated it all really, because of that reason. but now im a Navy Nuke (reactor operator) and use this **** all the time. craziness

[wilkin250r]

Originally posted by 400exrules
buuut, when you divide by a negative dont you flip the sign in an inequality?

Yes yes yes. Here is a very simple example. All numbers, no variable, so it's easy to understand.

We know that 4 is greater than 2, right? So we write: 4>2

We can see this because, in order to move from 2 to 4 on the number line, we have to ADD a positive number, so 4 must be greater. Likewise, in order to move from 4 to 2, we must subract.

Now, if we divide both sides by -1, it becomes : -4 > -2

But this can't possibly be true. -4 isn't greater than -2, it's LESS than -2. Why? Because we have to SUBTRACT a positive number to move from -2 to -4. If we have to subtract, doesn't that mean -2 is actually GREATER than -4?

So it should be: -4 < -2

If you divide by a negative, you must switch the sign.

[stumpleg]

Originally posted by 300exrida
5(-3x - 2) - (x - 3) = -4(4x + 5) + 13


I got x = -6

I think that is right. Doesn't take me a whole page, just 4 lines on the left hand side of notebook paper.

[wilkin250r]

Originally posted by 300exrida
5(-3x - 2) - (x - 3) = -4(4x + 5) + 13

Nope.

If you mutiply through all the parenthesis, you end up with:

-15x-10-x+3 = -16x+20+13

Combine like terms, you end up with:

-16x - 7 = -16x + 33

The "-16x" on both sides cancel each other out, so you get:

-7 = 33

Well, negative seven is NOT equal to 33, so you have an invalid equation. It doesn't matter what "x" is, because it cancels out. Plug in ANY number for x, the result still isn't valid.

[stumpleg]

Originally posted by wilkin250r
Nope.

If you mutiply through all the parenthesis, you end up with:

-15x-10-x+3 = -16x+20+13

Combine like terms, you end up with:

-16x - 7 = -16x + 33

The "-16x" on both sides cancel each other out, so you get:

-7 = 33

Well, negative seven is NOT equal to 33, so you have an invalid equation. It doesn't matter what "x" is, because it cancels out. Plug in ANY number for x, the result still isn't valid.


You multipied wrong. -4 x 5 is -20. You are right though. After looking back over my work, the x's cancel out, meaning number equals some other number, which ends up being something like
-6 = 1, which is false.

[JDiablo]

lol wilkin your to smart for some of us here,i wouldnt be suprised that you would get it

[trx400exat05]

hey i just took a test on that today!! soo if u need any help studying lemme know man and yeah when u divide by a negative number u switch the inequality lol

[400exc]

cjj is right, i got that too, i just learned that stuff in school lol