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Rekkuzo
Lord EmperorButto



Registered: 10/09/07
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Math help.
#7910169 - 01/21/08 03:48 PM (16 years, 11 days ago) |
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How do I figure out:
e^2x - e^x =6
How do I solve for x?
I'm stumped.
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Oracle Of Delphi
I, Phantom



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Re: Math help. [Re: Rekkuzo]
#7910177 - 01/21/08 03:50 PM (16 years, 11 days ago) |
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Sell Your Soul
Nutmeg shaman



Registered: 03/15/00
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Re: Math help. [Re: Rekkuzo]
#7910183 - 01/21/08 03:51 PM (16 years, 11 days ago) |
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Quote:
Rekkuzo said: How do I figure out:
e^2x - e^x =6
How do I solve for x?
I'm stumped.
e^2x = (e^x)^2 let z=e^x
z^2-z=6 Solve for z using standard quadratic methods.
Then: x=ln z
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learningtofly
Ancient Aliens



Registered: 05/21/07
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natural log is your friend
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fee
Im he who is the


Registered: 01/16/03
Posts: 18,238
Loc: amsterdam
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wtf does ^ stand for?
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blankk said to fee: btw you're a total fucking psychedelic pimp Turtletotem said: I want to become a sun worshipper, so next time an atheist smugly asks me where god is, I can point smugly at the sun and laugh my ass off. Then I drive away in my solar powered piece of shit car, cool stuff man. And then I go kill a bitch because the flaming orb in the sky told me to do so, and I don't know, oppress a few minorities here and there in the name of nuclear fusion? Religion is fun.
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Sell Your Soul
Nutmeg shaman



Registered: 03/15/00
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Re: Math help. [Re: fee]
#7910196 - 01/21/08 03:53 PM (16 years, 11 days ago) |
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^ means to the power of ..
Example: 5^3 = 5*5*5 and 6^4 = 6*6*6*6
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Rekkuzo
Lord EmperorButto



Registered: 10/09/07
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Yay, thank you.
I got ln(3)
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Edited by Rekkuzo (01/21/08 04:06 PM)
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Cepheus
Balance




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Re: Math help. [Re: Rekkuzo]
#7910221 - 01/21/08 04:01 PM (16 years, 11 days ago) |
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e^2x - e^x = 6.
log both sides:
ln(2x) - ln(x) = 6
using the laws of logs: ln(2x/x) = 6
and as andyistic said:
ln(x) = 6 x = e^6.
-------------------- "I only ever hope to reach equilibrium, in Nature's matrix, in line with the meridian" ~ Jehst
"...and I know that I have to keep breathing, as tomorrow the sun will rise, who knows what the tide will bring?" Free Spore Ring Europe Send any spare spore prints you might have and help the distribution
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Oracle Of Delphi
I, Phantom



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Re: Math help. [Re: Rekkuzo]
#7910224 - 01/21/08 04:02 PM (16 years, 11 days ago) |
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doesnt it mean to look at the post above, as in referencing it?
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Sell Your Soul
Nutmeg shaman



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Re: Math help. [Re: Cepheus]
#7910236 - 01/21/08 04:05 PM (16 years, 11 days ago) |
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Um, that's not what I said. Please check above, thanks.
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Rekkuzo
Lord EmperorButto



Registered: 10/09/07
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Thanks for the help. I achieved the correct answer of ln(3).
Is that the simplest way to do it?
>_< I really hate math sometimes. Just when I get the hang of integrating and shit they throw in stuff that requires the quadratic equation, which I barely remember.
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Sell Your Soul
Nutmeg shaman



Registered: 03/15/00
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Re: Math help. [Re: Rekkuzo]
#7910304 - 01/21/08 04:18 PM (16 years, 11 days ago) |
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Depends on how you define "simple". It is very straight-forward and prone to few errors. It sure beats punching random numbers into a calculator until something pops up that fits the equation.
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Cepheus
Balance




Registered: 04/19/06
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I must be missing something here 0.o
-------------------- "I only ever hope to reach equilibrium, in Nature's matrix, in line with the meridian" ~ Jehst
"...and I know that I have to keep breathing, as tomorrow the sun will rise, who knows what the tide will bring?" Free Spore Ring Europe Send any spare spore prints you might have and help the distribution
Open Source. Freedom. GNU/Linux Addicting is not a word.
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LeftyBurnz
Mr. I Eat Butthole



Registered: 06/21/05
Posts: 24,570
Loc: FL
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Re: Math help. [Re: Rekkuzo]
#7910383 - 01/21/08 04:28 PM (16 years, 11 days ago) |
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Quote:
Rekkuzo said: How do I figure out:
e^2x - e^x =6
How do I solve for x?
I'm stumped.
take it, add a crumple, and throw it the fuck out the window.
god i hate math.
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Sell Your Soul
Nutmeg shaman



Registered: 03/15/00
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You should see some of the equations that I see when I'm tripping balls.
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LeftyBurnz
Mr. I Eat Butthole



Registered: 06/21/05
Posts: 24,570
Loc: FL
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Quote:
andyistic said:
Quote:
Rekkuzo said: How do I figure out:
e^2x - e^x =6
How do I solve for x?
I'm stumped.
e^2x = (e^x)^2 let z=e^x
z^2-z=6 Solve for z using standard quadratic methods.
Then: x=ln z
how in the fuck....... did you actually do that or did you just type a bunch of shit?? lol
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LeftyBurnz
Mr. I Eat Butthole



Registered: 06/21/05
Posts: 24,570
Loc: FL
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Quote:
andyistic said: You should see some of the equations that I see when I'm tripping balls.
really? i see patterns and pictures.
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Sell Your Soul
Nutmeg shaman



Registered: 03/15/00
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I didn't forget everything from my days in school. The few brain cells that still work happen to be the ones that handle technical details.
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LeftyBurnz
Mr. I Eat Butthole



Registered: 06/21/05
Posts: 24,570
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where the fuck did you learn that? college? i never saw anything like that in HS. then again i was a tard at math.
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Sell Your Soul
Nutmeg shaman



Registered: 03/15/00
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Yes, college. They would never teach that to high school kids, especially the ones these days who only listen to rap. I don't know a single rap song that has lyrics which refer to logarithms.
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LeftyBurnz
Mr. I Eat Butthole



Registered: 06/21/05
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Loc: FL
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lmao. what year were you born anyway?
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Sell Your Soul
Nutmeg shaman



Registered: 03/15/00
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The year of disco, man! White collars over jackets all the way.
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Coaster
BaĘżal



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this is the best thread ive seen in a while
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Rekkuzo
Lord EmperorButto



Registered: 10/09/07
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Re: Math help. [Re: Coaster]
#7910573 - 01/21/08 04:58 PM (16 years, 11 days ago) |
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Yay, my homework is completed!
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LeftyBurnz
Mr. I Eat Butthole



Registered: 06/21/05
Posts: 24,570
Loc: FL
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Quote:
andyistic said: The year of disco, man! White collars over jackets all the way.
come on man, ill be 23 next month. i dont know what fucking year that is lmao. help a youngin out.
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Sell Your Soul
Nutmeg shaman



Registered: 03/15/00
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1977.
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Cepheus
Balance




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Re: Math help. [Re: Coaster]
#7910615 - 01/21/08 05:05 PM (16 years, 11 days ago) |
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Coaster, wtf am I missing here. You're some sort of maths guru. Its actually bugging me now.
-------------------- "I only ever hope to reach equilibrium, in Nature's matrix, in line with the meridian" ~ Jehst
"...and I know that I have to keep breathing, as tomorrow the sun will rise, who knows what the tide will bring?" Free Spore Ring Europe Send any spare spore prints you might have and help the distribution
Open Source. Freedom. GNU/Linux Addicting is not a word.
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DieCommie


Registered: 12/11/03
Posts: 29,258
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High school kids can do logarithms sometimes.
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LeftyBurnz
Mr. I Eat Butthole



Registered: 06/21/05
Posts: 24,570
Loc: FL
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Quote:
andyistic said: 1977.
do you have aim? if so, pm me your s/n.
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LeftyBurnz
Mr. I Eat Butthole



Registered: 06/21/05
Posts: 24,570
Loc: FL
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Quote:
DieCommie said: High school kids can do logarithms sometimes.
yeah im sure they do that shit in AP and whatnot. i wouldnt know though. i was never L33t enough for that. i took liberal arts math. haha. i know. call me retarded. whatever.
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Rekkuzo
Lord EmperorButto



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Re: Math help. [Re: Cepheus]
#7910694 - 01/21/08 05:23 PM (16 years, 11 days ago) |
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Quote:
Cepheus said: e^2x - e^x = 6.
log both sides:
ln(2x) - ln(x) = 6
using the laws of logs: ln(2x/x) = 6
and as andyistic said:
ln(x) = 6 x = e^6.
When you take the natural log of both sides you'd get: ln(e^2x - e^x) = ln(6) The function doesn't distribute as if it were a constant or a variable.
That's why I had to go back to algebra to solve the main part of the problem, which gave me:
z^2 - z - 6 = 0
BLAH QUADRATIC!!!
z = 3 or -2 and since z = e^x, x = ln(z); domain of ln(z) is z > 0, meaning ln(3) is the only correct answer.
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DieCommie


Registered: 12/11/03
Posts: 29,258
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Re: Math help. [Re: Rekkuzo]
#7910741 - 01/21/08 05:33 PM (16 years, 11 days ago) |
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also ln(2x/x) = 6 does not reduce to ln(x) = 6. It reduces to ln(2) = 6 which is of course not right.
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Jeebies


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Re: Math help. [Re: Rekkuzo]
#7910761 - 01/21/08 05:36 PM (16 years, 11 days ago) |
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He's right, ln(3) is the only correct answer.
I could do logarithms when I was a junior in high school. I guess I just took tougher classes, but it seemed like good stuff to know.
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Cepheus
Balance




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Re: Math help. [Re: Rekkuzo]
#7910768 - 01/21/08 05:38 PM (16 years, 11 days ago) |
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unless there is brackets (e^2x - e^x) I don't see why you can't:
e^2x = 6 + e^x
2x = ln(6) + x
x = ln(6)
Fuck knows. I'm still consolidating my learning.. so please correct me wherever its needed.
-------------------- "I only ever hope to reach equilibrium, in Nature's matrix, in line with the meridian" ~ Jehst
"...and I know that I have to keep breathing, as tomorrow the sun will rise, who knows what the tide will bring?" Free Spore Ring Europe Send any spare spore prints you might have and help the distribution
Open Source. Freedom. GNU/Linux Addicting is not a word.
|
Sell Your Soul
Nutmeg shaman



Registered: 03/15/00
Posts: 40,819
Loc: Over there
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Re: Math help. [Re: Cepheus]
#7910774 - 01/21/08 05:39 PM (16 years, 11 days ago) |
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Cepheus: You need to understand this:
log (a+b) does NOT equal log(a) + log(b)
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Liquidkick
H2O
Registered: 05/03/02
Posts: 2,635
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Re: Math help. [Re: Rekkuzo]
#7911131 - 01/21/08 06:36 PM (16 years, 11 days ago) |
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Wow. Totally thought you need to use Calc.
Its been so long since i have taken any math. Totally didn't even realize to use logs.
Sigh...
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learningtofly
Ancient Aliens



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Dude this is algebra 2 tops.
OP if you are still confused, look in your text book for practice problems or formulas, they should help immensely.
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Edited by learningtofly (01/21/08 07:02 PM)
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Rekkuzo
Lord EmperorButto



Registered: 10/09/07
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OP here, I'm not confused anymore; just more people are, lol.
Andyistic helped me w/ his first post.
And you're right, this is pretty much algebra. Initially, I just completely forgot to apply it to the problem, because I hadn't been in school for 2 years, but now I remember.
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Coaster
BaĘżal



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Re: Math help. [Re: Cepheus]
#7911687 - 01/21/08 07:56 PM (16 years, 11 days ago) |
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Quote:
Cepheus said: Coaster, wtf am I missing here. You're some sort of maths guru. Its actually bugging me now.
y yes i am
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Rekkuzo
Lord EmperorButto



Registered: 10/09/07
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Re: Math help. [Re: Coaster]
#7911852 - 01/21/08 08:21 PM (16 years, 11 days ago) |
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We should make this an official math help thread.
Officially.
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DieCommie


Registered: 12/11/03
Posts: 29,258
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Re: Math help. [Re: Rekkuzo]
#7911956 - 01/21/08 08:37 PM (16 years, 11 days ago) |
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You noobs could never help me with my l33t math classes  
j/k, there are actually some very mathematical individuals I have noticed here through the years... Diploid, Seuss, Trendal, The Cow are a few that come to mind (regulars of the science forum of course)
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Rekkuzo
Lord EmperorButto



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Re: Math help. [Re: DieCommie]
#8010302 - 02/11/08 07:17 PM (15 years, 11 months ago) |
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Ok, I'm bumping this up for yet another math question.
How do I go about finding the integral of 1/sinx?
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Tangerines




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Re: Math help. [Re: Rekkuzo]
#8010327 - 02/11/08 07:20 PM (15 years, 11 months ago) |
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1/sin(x)=csc(x)
Look in your book for the integral of csc(x) because it would be nearly impossible to actually find the answer yourself. It is just an identity you are supposed to know I believe.
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Rekkuzo
Lord EmperorButto



Registered: 10/09/07
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gotcha
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