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#1351 Re: Introductions » A new guy » 2006-04-11 03:27:43
welcome, creative guy!
#1352 Re: Help Me ! » Chance of Win Based on amount Players » 2006-04-11 03:23:27
each one of 9 players either win the expert or not.
set P(one novice loses)=p, it makes sense to say that for 9 players their ps doesn't interfere each other's and are equal(equally novices).
hence 0.48=p[sup]9[/sup]
for 6 novices, the expert winning chance would be p[sup]6[/sup]=0.48[sup]6/9[/sup]=61.3%
#1353 Re: This is Cool » Integral relationship » 2006-04-11 01:28:52
Cool tool, man. 
#1354 Re: Help Me ! » A mechanics question » 2006-04-11 01:21:45
if a vector ai+bj is parallel to the vector i+j, it means ai+bj=k(i+j)
since i and j are not parallel to each other, the only solution is a=k, b=k
Hence a=b
for your question
3t² - 2t + 8=5t +6
3t²-7t+2=0
(3t-1)(t-2)=0
t=1/3 or t=2
for c, the speed cannot grow up forever.
#1355 Re: Help Me ! » Line Integral » 2006-04-10 17:02:10
The second integral you mentioned is mainly for computing work done by conservative force. As you can see, the integrated is a dot product of work on a small piece F.dr, where F and dr are both vectors.
The first integral can be used to integrate f(t,t,t) |v(t)|, f(t,t,t) is displacement from origin, and if v(t) stands for velocity, then|v(t)| stands for speed, or the magnitude of velocity. i cannot figure out what the product means.
So you'd better use the second defaultly.
So far, i haven't encountered the situation to use your first integral.
#1356 Re: Formulas » Calculus (General) Formulas » 2006-04-10 00:42:20
and another fomula say it's -x/2 ???
#1357 This is Cool » Free Statistics Sofware ^-^ » 2006-04-09 18:58:21
- George,Y
- Replies: 0
#1358 Re: Help Me ! » in the circle » 2006-04-09 13:23:25
4/X+3=X
4+3X=X²
(X-4)(X+1)=0
X=4 and radius r=√x=2
center is O, (0,0)
#1359 Re: This is Cool » Horraaaaaay!!! :-d :-d :-d » 2006-04-09 13:19:28
Congratulations mikau ! ! !
cool computer guys, can java make faultless Operating System instead of Windows?? 
#1360 Re: This is Cool » The Shape of a Suspension Bridge's Main Cable » 2006-04-09 13:11:30
Liquid-mirror telescope
When liquid spins, it makes a parabola surface. and that's a good stuff for astronomors
Liquid-mirror telescope set to give stargazing a new spin
http://www.europa.com/~telscope/LMT.txt
it's really amazing to see these inventions are made little by little rather than spontanously.
#1361 Re: This is Cool » Euler's forumula » 2006-04-09 13:05:15
p²-10p(1-p)+5(1-p)²=0 corrected
16p²-20p+5=0
p= (20±√80)/32 = (5+√5)/8 = (10+2√5)/16
1-p= (3-√5)/8
cos(18°) = √p or=+√p
since no one can solve that out
i just compute cos(36°) = 2p-1 = (1+√5)/4 , cos²(36°)= 1-previous²
and
#1362 Re: This is Cool » Implicit Graphs » 2006-04-09 12:43:17
uh, that may explain the Fibonacci sequence's DYNAMIC!
#1363 Re: This is Cool » I disagree with » 2006-04-09 12:37:32
#1364 Re: This is Cool » Cold Fusion » 2006-04-09 12:35:49
but solar power is probably the way to go as the energy from the sun is either used or just beamed off redundantly into space and there's more than enough of it (for the next 13 billion years or so at least)
solar power really is a great substitude.
if a city is satisfied by solar power already, it won't seek for nuclear power.
still, that doesn't hold for a reason against exploring the cold fusion.
Human's need is endless
#1365 Re: This is Cool » I disagree with » 2006-04-09 04:31:24
Ricky wrote:
"George, now you are going into the absurd.
0.111.... has no complex part, and thus, it must be part of the reals."
actually, the ultimate disagreement is that i deny such an expression a number. because i cannot calculate it out, nor can i say it's stable. the only way to say it's stable is by inferal of Reached infinite thing. And i deny this concept because of subjectivity. see #43
#1366 Re: This is Cool » Euler's forumula » 2006-04-09 04:24:17
cos(180°)=
cos(45° )[sup]4[/sup]-6cos(45° )[sup]2[/sup]sin(45°)²+sin(45°)[sup]4[/sup]
=1/4-6(1/4)+1/4=-1
0=cos(90°)=cos[sup]5[/sup](18°) -10cos³(18°)sin²(18°)+5cos(18°)sin[sup]4[/sup](18°)
define p=cos²(18°) hence sin²(18°)=1-p
p²-10p(1-p)+(1-p)²=0
#1367 Re: Help Me ! » in the circle » 2006-04-09 04:07:53
A²X²+2ABXY+B²Y²=4XY-3X²+1
(A²+3)X²+(2AB-4)XY+B²Y²=1
∴2AB-4=0 AND A²+3=B² AND CENTER IS (0,0)
X²/P²+Y²/P²=1 WHERE 1/P²=A²+3=B²
X²+Y²=P² SO THE RADIUS IS P
A=2/B, 4/B²+3=B²=DEF=X
4/X+3=X
you can go on from here
#1368 Re: Help Me ! » Latex » 2006-04-07 20:17:14
yeah, we can type matrix now!
\displaystyle to enlarge the []
\left[ to define left bracket
\begin{array}{c} to define matrix centered
1,0,0\\0,1,0\\0,0,1 entries and rows
\end{array}
\right]
#1369 Re: Help Me ! » proof » 2006-04-07 20:12:20
at least one p,that g(p)>zero or equal to zero or g(p)<zero or equal to zero,is true. --do you mean g(p) cannot be (-1,8,...)type?
g is a vector function?
at least one-- i can't use this special condition, lol
#1370 Re: Help Me ! » a b + c d = 6 && a c - 3 b d = 5 » 2006-04-07 20:07:00
yes, you'r right. sufficient but not necessary. at least one of the original equation have to be contained.
from a c - 3b d = 5, ac-5 contain 3 , ac elem {8,11,14...}
#1371 Re: This is Cool » Euler's forumula » 2006-04-07 18:09:44
It really has an great application!!
Beyond simple trigonometric formulas
It can be used to derive cos(nθ) and sin(nθ) by cos(θ) and sin(θ).
...last part ,+ -uncertain,
when n is even,or
when n is odd
#1372 Re: Help Me ! » a b + c d = 6 && a c - 3 b d = 5 » 2006-04-07 03:13:47
(a+d)(b+c) = 6+5+4bd
contains all the information of a b + c d = 6 and a c - 3b d = 5. and it might be a path. i'm new in this field, and what i could do is shifting, to see if it has been made simplier....
#1373 Re: Help Me ! » Latex » 2006-04-07 03:09:50
#1374 Re: This is Cool » Cold Fusion » 2006-04-07 03:07:32
He may not want his findings published so that he can make some money.
Sorry to say that, i guess i've seen too many movies. 
#1375 Re: This is Cool » The Shape of a Suspension Bridge's Main Cable » 2006-04-07 03:04:24
Thank you for your appreciation. Thank you krassi_holmz for your reference.
Let's take a break and appreciate some history.
The first modern suspension bridge ever built is Brooklyn Bridge, which connects Manhatten and Brooklyn, New York. The idea came from a German immgrant engineer, John Augustus Roebling . Avant as he was, he prepared 2 years from 1867 for every detail before start, and worked for 14 more years before he died of an infection.
His son Washington, also an engineer and bridge builder, took over his father's dream. He and his wife co-si[ervised the construction and completed the bridge.
The Brooklyne Bridge
Total Span: (Measures the distance between the two anchorages.) 3,455 feet
Main Span: (Measures the distance between the two towers.) 1,595 feet
Height of the Towers: 276 feet
Engineer(s): John Roebling, Washington A. Roebling
Cost: $15 million
Washington and his wife