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Math Question


Hey I have 3 little simple math question if anyone can help. It's just lines that I dont understand.


Y is a line in a complex plan that is determined by the origin and the complex number given by the scalar product of 2 vector x and y. It is denoted by (x,y)

Now sigma varies over the line Y' (Y' is symmetric to Y by the x-axis) so that sigma=tz (t is real)
z= complex conjugate of (x,y)(with the line over) / absolutevalue((x,y)). It is the unit vector

everything is good but now they say
sigma*(x,y)=t*abs(x,y). They say this is real. I dont understand

E(j=0,p) = summation for index j from 0 to p
P^(j)(u) is a polynomial in u with power j

E(j=0,p)E(l=o,p) 1/(j!l!)P^(j)(u)Q^(l)(u)*(sigma-u)^(j+l) gives
E(k=0,2p) E(j=0,k (1/(j!(k-l)!)) P^(j)(u) Q(k-j)(u)^k


There exist an ''n'' so that (n-1)x is smaller or equal than.. y.. smaller than nx
for arbitrary x real positive and arbitrary y

n is greater than 1/h. 1/n is smaller than h
there exist an integer m such as
m/n smaller or equal to ..a.. smaller than (m+1)/n. (this is a modified version of the theorem above)

now ''clearly'' (well not for me)
(m+1)/n -a is smaller or equal to 1/n is smaller than b-a.

the right side of this is obvious (stated before) but I dont see why (m+1)/n -a is smaller or eq. than 1/n

sorry if this is not entertaining. I'll post it in a math forum also.


scan question for better legibility. can't promise I can help tho, I'm on coop right now so my math is rusty


I think what they are trying to get at here is |x+j*y| = (x+jy)(x-jy)

Therefore the magnitude of a complex number is equal to the product of it with its complex conjugate (x^2+j xy - j xy - j^2y^2) = (x^2+y^2) which is a real number.

Complex conjugates will be symmetric about the real axis (x). This is invariable to a scaling such that a*|x+j*y| = a*(x^2+y^2)


Ermm...what he said. :stuck_out_tongue:


Answer is `bout tree-fiddy.


Where's Planet Fitness now?




I'll take this opportunity to ask, "WTF is a Jasmincar anyway?"


The quadratic sum of the equals, minus the offset complex matrix^3, over the root of the moon.


I think


I see what you did there.


Glad you do, because to be honest I have NO idea what is going on in this thread :wink:

Much respek to the OP and the posters who are actually able to help him. Wow. I always thought I was smart, but I guess I will have to convince myself I am a different kind of smart and pretend it carries over.


Err whats the meaning of life again?


there is an error. When I wrote this in 2) I meant The length 1(x,y)1 instead of the absolute value of (x,y) which both have the two bars.

I'll be back later


Oh shit, that completely changes everything!

Sorry, still got nothing for ya


Yes. The product of a complex number with its conjugate is always real.

Good answer.


Found an error in my answer:

|x+j*y| = sqrt(x^2+y^2)

||x+j*y|| often refered to as the norm (or L2 norm as we are in 2D cartesian space) is the x^2+y^2 and it can be interpreted as the power in a signal. It will pop up a lot when doing detection or estimation of a deterministic signal in noise, specifically in terms of describing performance for various SNRs, where SNR is power of signal/power of noise.

What are you studying Jasmincar?


You know that m/n <= a < (m + 1)/n. If you just look at the left hand part, and add 1/n you get
m/n + 1/n <= a + 1/n. Subtracting a from both sides we have m/n + 1/n - a <= 1/n, or
(m + 1)/n - a <= 1/n as required. You can treat <, > etc like an = for adding and subtracting, you just need to be careful when multiplying...




ok so

sigma=tz= t*(complexconjugate(x,y)/I(x,y)I)

but they write sigma*(x,y)=t*I(x,y)I

I still missing something