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**Posts by jk22**

I have a similar problem but over real numbers : P(x) = 2x^4 + x^3 - x^2 - x

i can get x(2x^3 + x^2 - x - 1), but then i cannot find the next real root with 3rd degree formulas

and cannot find another method. thanks.

**jk22**- Replies: 1

If taken a number in basis 10, let say 10(10)

in basis 4 it is : 10=4*2+2=22(4) (notation)

hence the number in a smaller basis is *bigger* if it were in basis 10

however let say we had 2.5(10) in basis 10, then

2.5=2+1/2=2+2/4=2.2(4)

this time the number in the smaller basis is *smaller* than if it were in basis 10

Hi dave and bobby,

about this topic I thought that about the case of a blind person, If I close the eyes for example, I could not see 3d dimension, but feel them locally, the touching sense, and hence could never be sure/globally that suddenly a "passage" would not exist in an other dimension, by following a certain trace ?

Or what about if we moved in a 3d "tunnel", how to know if this tunnel itself were more than in 3 dimensions ?

thanx.

Hi John,

thanks for your info. Did you get 29% from a calculation ? I have a video about but I can't up load it, maybe it's seeable at : https://docs.google.com/leaf?id=0B9pGxyM9yy2fNDMxMjgyYWQtNjQ0Ny00NGYzLTllOTUtMzFkNmIwNGY1MTky&hl=en

Hi bob and heirot,

what about the reverse case : a hexagon in a square ? Only eccentric case exist ? I suppose it's possible to unscrew.

Hi Bob,

yeah it's dumb, it's a link to google docs I have, but only me can see them.

Does there exists a 4-point eccentric case ? I cannot figure it out.

bye.

**jk22**- Replies: 2

Hi all,

I have a small problem I would like to solve :

Suppose 2 same soap bubbles on a table :

a) glued at each other with a plane separation, what is the volume and shape ?

b) if the separation is made away, forming a unique bubble, what is the final volume ? (note : Vfinal>V1+V2)

Bye.

Hi, bob,

i thought there was a domain, but couldn't figure it out with geometry. Maybe it's the first case i fell upon, I used the sine theorem.

d/sin(60)=b/sin(180-60-45) [hope you can see the pics]

Do you think other possibilities with 3 touching spots are not possible ? I mean this would imply non concentric centers, and I don't know if it's possible to (un)screw in this eccentric case ? ( I could manage to upload pictures) :

I'll look at the equation and tell you if i manage to understand these.

cya.

Hi heirot, nice to meet you,

I think I found a case with a=2*sin(60)*sin(45)/sin(75)*b ?

cya.

Hi, nice to meet you,

we could start like : d/dx=d/dz*dz/dx+d/dzbar*dzbar/dx=d/dz+d/dzbar

Hi,

yes, or 0^0.

Studying false proof can help not making them. Some pitfall are :

a) right deduction, but hypotheses aren't (Sometimes proven after), hence we can deduce nothing

b) the proof uses the result to be proven

Hi bob,

f you find 24 elements in a closed set (ie. no more elements generated by those 24 in any combination) you've got your result.

I finally got the 24, but with a computer program, after 100 multiplication, only 24 were different. Anyway, Thanks for your explanation of why it was not 48.

I haven't found yet the dimension, taken this 9 element function of 24 variable, how many are independent : it should be 4 or 8, but i need to write a code again (could it be that there were 9 linearly independent matrices in this set ?)

almost, I read we put complex numbers in the form of real matrices, but this "isomorphism" is maybe already too descriptive of the symbol i ?

Hi,

we have not 1=2, except if units are e.g. $ and £ in the year (to find, e.g. in the y 1976, or 1978 http://www.miketodd.net/encyc/dollhist.htm)...1£=2$ were at some time of the story of humanity.

but we were allowed to write

2 is equivalent to 0 (modulo 2)

divide by 2 and

1 is equivalent to 0 (modulo 1).

Hi, ok.

By dimension I meant : the minimal number D of elements, so that a linear combination of these independent elements (now with a sum) give all the elements.

Anyhow in this case the field of coefficient cannot be continuous, but maybe

which were not so interesting.Hi, thanks for the explanation.

Now that I have the number of elements, I tried to find the concept of dimension, but I don't know how to find it, it should of course be <=9.

For the second question I found :

[1 -1]

[2 -1] has determinant 1 and square to -1, but it's not a good example, since this 3 axes were broken at origin (x->(1,2), y->(-1,-1))

Hi, thx.

I had another question : Suppose we find 2 linearly independent i=sqrt(-1), with 2x2 matrices, let say I1, I2. I don't know If their product is spanneable by {1,I1,I2}, but if it were the case, were this a sufficient condition to build an algebra ?

----------------------------------

(there is more time than patience, but the world is imaginary small)

Hello bob,

yes it is, however i couldn't find the cardinality of the group of rotation of 90 around xyz which i suppose to be 48.

Hi, nice to meet you.

I looked at the Kronecker's method, but don't understand how it goes

for example : f(x)=x^8-x^7+x^5-x^4+x^3-x+1

I have f(0)=1, f(2)=151, f(-2)=331

if I look for a polynomial g(x)=ax^2+bx+c, fitted with the values above, got :

g(0)=1=>c=1

and a=60, b=-45.

and the following of it would be : if the coefficient are integer, and the discriminant <0 it should be dividable ?? (which here is not the case, since delta>0)

**jk22**- Replies: 10

Hello,

If I consider 2 rotations in space : Rx(90°) and afterwards Ry(90°) of the vector (1,1,0)

it gives : (1,0,-1) (as by matrix multiplication Ry*Rx)

but considering that the first rotation, Rx, turns the y-axis, leads to (0,1,1)

Is there an easy way to get the latter with matrix operations, can it be shown generally, that it will be Rx*Ry, hence :

Is it that the resulting rotation of two rotations rotating the axis too, were the inverse order matrix product, is it the same as Euler-angles ?

b) do you know how many elements the group of all composition of rotations of 90° around x,y,z axis contains ?

Thx.

Hi, nice to meet you.

can we say : to be sold 60 apples at 25$,

6 apples at 2.50$ (or 5 at 2.083$, since 25$/12 non equals 2)

3 at 1.25$ but then w/o caring about the sort of apples.

**jk22**- Replies: 2

Hi all, I'm new to this forum,

suppose that by telepathy it could be found if the price would be lowered or increased, so that a stability on some domain can be found,

what will the effect of a rat running on the keyboard ? It could not be predicted by telepathy, and could induce chaos

programmers have noticed it's much easier to program an automatic insult generator than a worship generator.

and that death of people was always the same : enough money was put in the bet, that it was worth programming the death of with certainty : take bill with the more money corresponding, say the cause.

Hi, nice to meet you.

for #1 could we write :

let c=0 :

let a=0 : , the square of any number is 0

-------

from

:right-multiply with a :

let a=1,

but since the square of b is 0 : , which can be written :

Hi, nice to meet you.

i think it works as distributing r1 i1 on comp2 :

comp1*comp2=(r1+i*i1)*(r2+i*i2)=r1*(r2+i*i2)+i*i1*(r2+i*i2)

=r1*r2+i*r1*i2+i*i1*r2+i*i1*i*i2=

=(r1*r2-i1*i2)+i(r1*i2+i1*r2)., since i*i=-1

or

realpart(comp1*comp2)=real1*real2-imag1*imag2

imagpart(comp1*comp2)=real1*imag2+imag2*real2

cya.

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**Posts by jk22**