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#1 Guestbook » Achievement unlocked » Yesterday 20:48:56

Agnishom
Replies: 1

I am the only registered member who has the highest number of threads in the guest book.

#2 Guestbook » Warning guys! » Yesterday 20:47:50

Agnishom
Replies: 1

I have enabled autocorrect. You will now see my spellings improve but my grammar will stop making sense

#3 Re: Maths Is Fun - Suggestions and Comments » Separation of Variables » 2014-08-26 20:54:21

Nice page.

Now, how do I use this to get the time-independent equation?

#4 Help Me ! » Interesting property of 7! » 2014-08-25 05:46:38

Agnishom
Replies: 3

How many solutions of x! = nPr are there such that n and r are different?

#6 Re: Introductions » Hi » 2014-08-23 00:49:26

Welcome to reality.

What os your favorite color?

#7 Re: Science HQ » find the force » 2014-08-22 13:45:39

The reaction force between m and M is 5kg*5m/s^2

To balance the friction, you must give a force of 5kg*5m/s^2*0.4

#9 Re: Help Me ! » Apparently, math becomes m a t h wherever it is used ... » 2014-08-21 23:08:32

bobbym wrote:

The site already has one.

yes, and the name of that program is bobbym.

Now, has this guest posted here before at all?

#10 Re: Dark Discussions at Cafe Infinity » Problems with discipline » 2014-08-21 03:05:12

You cannot teach a man anything, you can only help him find it within himself......bob bundy

#11 Re: Dark Discussions at Cafe Infinity » Problems with discipline » 2014-08-21 02:27:49

Brilliant is a competition site, rather than education. For that purpose, I wil recommend mathopolis, mathisfun and expii.

Ask me if you need a refferal code for expii

#12 Re: Introductions » hi » 2014-08-20 12:06:20

I do realise it now, bob. Thanks smile

Hi iluvdogs;
Who is your favorite dog?

#13 Re: Introductions » hi » 2014-08-20 02:11:22

Hi;

What is your favorite color?

#15 Re: This is Cool » Did you know this about any Non-Prime? » 2014-08-18 04:36:09

only when

Are you saying that if x - y = 1, then x^2 - y^2 is a prime?

#16 Re: Help Me ! » PerpendicularQ » 2014-08-17 03:03:56

Solution

pZGPc1A.jpg
Let us call the curves c1, c2 and c3

It is evident that:

c1 = (cos t, sin t, 0)
c2 = (cos t, 0, sin t)
c3 = (0, sin t, cos t)

[I am considering the circles to be centered at the origin and of radius 1. This is just to make the algebra simple]

You wanted me to prove that c1 intersects c2 making an angle of pi/2 and c2 intersects c3 making an angle of pi/2 and c3 intersects c1 making an angle of pi/2

Consider the intersection of c1 and c2. At this point, c1(t) = c2(t)
Or, (cos t, sin t, 0) = (cos t, 0, sin t)
Solving, you get t = 0

Now, c1(0) = c2(0) = (1, 0, 0)

Differentiating the curves,
c1' = (-sin t, cos t, 0)
c2' = (-sin t, 0, cos t)

At t=0, c1'(0) = (0, 1, 0) and c2'(0) = (0, 0, 1)

Let x1 be the tangent of c1 at the intersection point
We have, x1= c1(0) + t(c1'(0)) = (1, 0, 0) + t(0, 1, 0) = (1, t, 0)

Let x2 be the tangent of c2 at the intersection point
We have, x2= c2(0) + t(c2'(0)) = (1, 0, 0) + t(0, 0, 1) = (1, 0, t)

By the angle between c1 and c2, we obviously mean the angle between x1 and x2.
Let that angle be  θ

x1 . x2 = (1, t, 0) . (1, 0, t) = 1*1 + t*0 + t*0 = 1

|x1| = Sqrt[1+t^2]
|x2| = Sqrt[1+t^2]

At the intersection point, t=0. So,


Similarly, you can go on proving the same thing for the two other intersection points (but that has been left to the reader as an exercise tongue)

QED

#17 Re: Help Me ! » General solution for this differential equation?? » 2014-08-16 13:45:50

(1/12)y^4 = (1/2)y^2 - y + (1/2)C[1]y^2 + C[2]y - C[3]

Is that the answer?

#18 Re: Computer Math » Post Beautiful Plots » 2014-08-16 02:11:13

Context Free Code:

CF::Size = [s 225]
 
startshape leggo
 
shape leggo {
CIRCLE[s 36]
 
loop 180[r 2]
vein[s .6 hue 65..180 sat .3 b .8 x 12 y 12	]
 
loop 206[r 1.75]
myveins[hue 160..250 sat .3 b .7 x -40 y -40] //Comment out
this line for some trippy shizz
 
loop 20 [r 14..20]
yomama[s .8 hue 0 sat .7 b .7 a -.5 x (-71..-68 )y
(-71..-68)]
 
mycircle[]
}
 
shape yomama
rule .99{
CIRCLE[]
yomama[s .995 x -.1...5 y -.1...5 r -10..10]
}
rule .01{
CIRCLE[]
yomama[s .995 x 0...5 y 0 ...5]
yomama[s .6 r -60..60]
}
rule .05{
CIRCLE[]
yomama[s .995 x 0...5 y 0 ...5]
yomama[s .6 r -60..60 a -.8]
}
 
shape myveins{
vein[]
loop 10 [r 18]
vein[s .2 r -85]
}
 
shape vein
rule .99{
CIRCLE[a -.2]
vein[s .99 x 0...5 y 0 ...5]
}
rule .0775{
CIRCLE[a -.2]
vein[s .99 x 0...5 y 0 ...5]
vein[s .6 r -60..60]
}
 
path mycircle{
myrad = 100
 
MOVETO(0,(-myrad))
ARCTO(0,(myrad),myrad)
ARCTO(0,(-myrad),myrad)
STROKE(1)[]
}

full_3434.png
by DackAttack

#20 Re: Introductions » Olinguito » 2014-08-15 00:54:30

Welcome to reality.

What is your favorite color?

#21 Help Me ! » Iterated expectation » 2014-08-14 01:55:52

Agnishom
Replies: 1

Somebody teach me iterated expectations please?

#23 Re: This is Cool » How to find whether a given number is prime or not? » 2014-08-12 06:43:00

Step 2: Test whether A is divisible by any prime number less than  K. If yes A is not a prime number. If not, A is prime  number.

What happens if A is divisible by K?

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