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#226 Re: Exercises » Areas and Volumes (Moderate difficulty) » 2006-11-26 06:40:03
very nice exercises, altough i get a different answer on problem 1a.
edit: i get way different answers on number 2 too, but i guess i maybe missunderstood it...
#227 Re: Exercises » Geometry Problems » 2006-11-26 05:55:57
very cool exercises. could you please make more like problem nr 6? 
and btw in nr 6 you said in the text that the sides are 9 and 6, but in the solution 18 and 12...
#228 Re: Help Me ! » is this function possible » 2006-11-07 04:17:31
looking like this..
edit: i realized my function wont work, but i hope you get the point...
#229 Help Me ! » is this function possible » 2006-11-07 04:14:45
- Kurre
- Replies: 1
is it possible to do a function with an infinitive amount of extremal points?(not using cos, sin or tan) a function that continues to turn around with a formula like....this?:
#230 Re: This is Cool » What you think about this IQ test? » 2006-11-04 22:44:11
also got bored on the last ones, got a iq of 128...some qestions were indeed really tricky, anyone know what to do with the mazes in the end?
#231 Re: Puzzles and Games » Devanté's Riddle House » 2006-11-04 22:11:54
#232 Re: Exercises » Simplifying Simple i Terms (Intermediate) » 2006-10-20 21:03:28
Kurre wrote:how can i^3 be -1, if you dont know the value of i?
we do, i = √(-1)
why?
#233 Re: Puzzles and Games » Word puzzle, yet again » 2006-10-18 18:42:54
I think Hebrew has extra vowels, if I'm not mistaken.
isnt it hebrew that excludes all vowels??
#234 Re: Puzzles and Games » Word puzzle, yet again » 2006-10-17 05:56:58
try to include Y too, its a vowel at least in the swedish alphabet
:
#235 Re: Exercises » Simplifying Simple i Terms (Intermediate) » 2006-10-12 07:53:36
how can i^3 be -1, if you dont know the value of i?
#236 Re: This is Cool » My Mind is Playing a Trick on Me! Wait, No It's Not. » 2006-10-11 02:43:53
http://www.youtube.com/watch?v=ubSzmxkeZOc
this one is better 
#237 Re: This is Cool » I disagree with » 2006-10-10 06:59:46
if you have a number a, no matter how many times you add 1/inf to it, its still 'a' and it does not change. Dont think of it as adding a one to the end of an infinate chain of 0's. Thats trying to think of infinity and infintisemals as numbers. there not.
just noticed a funny thing here.
1+n(1/infinty)=1
and
1+n*0=1
but if n= infinity, you add an infinty amount of 1/infinity, wouldnt this look like:
1+infinty(1/infinity)=1+infinity/infinity=1+1=2
but
1+infinity*0=1+0=1
1<2
1/infinity > 0
thats if infinty can be used as a number, which i guess it cant, but still...funny
#238 Re: Puzzles and Games » Conundrums » 2006-10-06 20:05:52
#239 Re: Puzzles and Games » Conundrums » 2006-10-06 11:19:32
#240 Re: This is Cool » I disagree with » 2006-10-06 11:05:19
if not 0.999... = 1 , then 1.000... isnt = 1 since there could be a 1 or a 5 or any number at the end of these infinite zeroes...
and also, as said, 0.999... = 9/10+9/10^2+9/10^3+...+9/10^n
then the difference (h) between 0.999... and 1 must be 1/10^n
but since n = infinity, h=1/infinity=0 (since 1/0=infinity, 1/infinty=0)
so the difference between 0.999... and 1 is 0, and therefor 0.999...=1
#241 Re: Exercises » About the Exercises » 2006-10-06 02:39:28
We need another word for Advanced!
could be "Professional"
#242 Re: Exercises » About the Exercises » 2006-10-04 00:24:12
you could have the categories sorted by the maths difficulty level on the exercises..
#244 Re: Puzzles and Games » Devanté's Riddle House » 2006-10-02 04:46:47
#245 Re: Puzzles and Games » function machine » 2006-09-30 20:01:47
if im not mistaken you get a deja vu because your eyes accidently sends two signals to the brain so when the second signal reaches the brain you think you have seen it before...or something like that
#246 Re: Exercises » Simplifying Irrational Numbers » 2006-09-29 19:50:37
am i correct?:/
#247 Re: Puzzles and Games » alpha puzzle » 2006-09-29 03:04:50
do they need to be different words?
#248 Re: Puzzles and Games » Rectangle !! » 2006-09-28 00:45:03
if you let the original rectangle be a square:
if you let the result be a square:
#249 Re: Puzzles and Games » The Prisoners and the Lightbulb » 2006-09-24 07:34:01
okey i was wrong, it was possible. I found a solution
should i wait with posting it? or should i email it?
#250 Re: Puzzles and Games » The Prisoners and the Lightbulb » 2006-09-24 01:05:17
i think it is impossible.
since the lightbulb only have 2 "values", on or off, one of these must mean that everyone have been there or not. which means that someone before must know by looking at the lightbulb that he is the final prisoner to visit the room, so he can tell the next one to ask the aliens. but to know that, a prisoner before must have decided the lightbulbs state (by looking at its previous state) to tell the next prisoner, to tell the next prisoner to ask the aliens...but to know that, a prisoner before etc etc
which in my logic says that the light bulb must have 100 states, one for every prisoner.
the only solution i can come up with is that every prisoner screws(?) the lightbulb from its ground 1/100 of the total length the first time they visit the room, so the one that can remove the lightbulb asks the aliens .
or just bribe the aliens...
edit: i just saw that the time between every visit is set to one hour. How long time do every prisoner have in the room? if they stay for more than one hour, do they get company?
and also dross, i hope the solution doesnt have anything to do with the lightbulb being warm or not??