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#101 This is Cool » second earth » 2007-04-26 09:36:14
- Stanley_Marsh
- Replies: 2
http://news.bbc.co.uk/1/hi/sci/tech/6589157.stm
It's really exciting having found a most earth like planet . I bet there're alien on it .
The problem is , How can we travel a distant of 20.5 light year?
#102 Re: This is Cool » Other Universes and Alien Races » 2007-04-26 09:32:00
I say that there is another Universe, a one which is the exact oppisite of everything in this Universe.
One flaw about this is , that if that universe is the opposite of ours , then If we can't travel to that universe , that will mean that the ppl from the opposite universe can travel to our universe. It will be a one way passage ,right?
#103 Re: Help Me ! » Need proof. » 2007-04-26 09:27:03
#104 Help Me ! » Need proof. » 2007-04-25 16:03:35
- Stanley_Marsh
- Replies: 7
#105 Re: Exercises » Janes exercises » 2007-04-25 12:15:42
Don't know it will work tho.
If a ,b,c lie in the same straight line , We have a-b=zc , b-c=xa ,c-a=by , Add them together , get xa+yb+zc=0 ,
#106 Re: Help Me ! » Set , Help » 2007-04-25 11:36:19
Thx ,Jane
#107 Re: Help Me ! » Set , Help » 2007-04-25 02:48:41
About question 2 , if it asks what are the equivalent classes .
Then , it's A={m-n=0(mod 3)} , B={s-t=1 (mod 3) }, C={a-b = 2 (mod 3) }, Since the union of A,B,C = Z , right???
#108 Re: Jokes » Do You Know ...how These Names Came About » 2007-04-24 09:25:03
IBM - Industrial Biggest Mistake. lol
#109 Re: Help Me ! » Set , Help » 2007-04-24 09:21:36
I don't really understand what is maxiaml linearly ordered subsets , and the way to find it.
It says I need to use Hausdorff Maximality Principle , I have no idea.
#110 Re: Help Me ! » Matrix » 2007-04-24 06:25:39
A has inverse , B has inverse , is there a proof for A+B?
#111 Help Me ! » Set , Help » 2007-04-23 19:46:08
- Stanley_Marsh
- Replies: 9
To question II , I did this .
Check it please.
#112 Re: Help Me ! » Matrix » 2007-04-23 18:10:27
One more question , if A , B have inverse ,so does A+B?
#113 Re: Help Me ! » Matrix » 2007-04-23 12:50:42
I've got it , thanks .
#114 Help Me ! » Matrix » 2007-04-23 09:34:41
- Stanley_Marsh
- Replies: 9
The asscociative law is (AB)C=A(BC) , what happen if more than three matrix , ABCD=A(BCD)=A(BC)D????
#115 Re: Help Me ! » derivative » 2007-04-21 11:27:09
Use vectors~
To prove sin(A-B) , just let A( cosA, sinA) ,B(sinB , cosB)
#117 Re: Dark Discussions at Cafe Infinity » My soon to be headless fan art drawing » 2007-04-20 05:01:57
Try to put on faces. 
#118 Re: Dark Discussions at Cafe Infinity » Rida's card factory » 2007-04-20 05:00:46
I like it when you draw in Comic style
#119 Re: Dark Discussions at Cafe Infinity » What's you fav part of songs lyrics. » 2007-04-20 04:57:14
Belive I Can Fly - It's real classic song.
Espeon , Can u identify this Japanese song for me ? http://www.youtube.com/watch?v=swOqSJ4GJjU&mode=related&search=
#120 Re: This is Cool » Other Universes and Alien Races » 2007-04-20 04:54:46
Paralell universe~ hehe
#121 Re: Help Me ! » infinity » 2007-04-19 12:36:09
The characteristic only exists in math lol ~one thing with two opposite character.
#122 Help Me ! » infinity » 2007-04-19 09:18:40
- Stanley_Marsh
- Replies: 5
the set of all rational numbers is countable , but set of rationals seems to have "greater" infinity than the set of positive integers does.
The concept of infinity is really vague. Is the R^1 both closed and open a math contradiction ? Will it lead to some crisis ?
#123 Re: This is Cool » Other Universes and Alien Races » 2007-04-19 03:52:27
Maybe live in different dimensions.
#124 Help Me ! » FreeCell » 2007-04-18 18:07:48
- Stanley_Marsh
- Replies: 3
I believe most of you have played the card game FreeCell . I have played a hundred games of it , and I believe it's always solvable. I wonder is there a way to prove it.
#125 Re: Help Me ! » confuse » 2007-04-18 15:17:05
OH yeah , I always treat a set as an interval~ it can be serveral.