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Hi bobbym thanks for replying . I guess the link that you gave above have cleared all my doubts and concepts I interested in. I appreciate your effort .
Hi, I am currently taking a course on number theory and was doing some revision on my own. There is one part of the topic that my lecturer has only briefly touches on but has however, sparked my interests.
It's mentioned that for some recurring decimal like 1/23, 1/17 has the property that it will follow the same cycle for any integer multiple of it eg:
and
however recurring decimal like 1/13, 1/37 does not exhibit this trait. May I know what the reasoning behind this is? I really keen to know.
Thanks for your time and I will appreciate if anyone could explain this to me or at least point out on where I should research on to find out the answer.
The series that you are refering to is:
which can be simplified to:
using the formula for geometric series.
I am just doing some practices questions from my textbook on my own by the way.
Hi bobbym thanks for the link. However after following through the working I end up having to solve a 15 degree polynomial:
Are there any easier method?
Well I have problem understanding this question as I don't even know where to start. Would appreciate if anyone could sheath some light on how to tackle this question or at least give some hint on where to start.
The Z Corporation issues a 10%, 20-year bond at a time when yields are 10%. The bond has a call provision that allows the corporation to force a bond holder to redeem his or her bond at face value plus 5%. After 5 years the corporation finds that exercise of this call provision is advantageous. What can you deduce about the yield at that time? (Assume one coupon payment per year.)
Thanks. So as to clear thing up if we are given
are we also right to say that ? and also, implies ?Hi Avon, thanks for the help I appreciate it . Anyway, as for the last part of my question I do understand that
implies that , which is enough to show that the poles of g do not lie in the open unit disk. However, to my understanding will never implies because is exactly equal to 1 and never larger.Please advise.
Q1:
Evalute
Where C(0,6) is the positive oriented circle |z|=6 and
I understand that for this question we need to use the Argument Principle in which
However, the solution are given something like:
Zeros in
are:Therefore
My question is, why as for the sin(z) term we only take 0, pi and -pi? If we are considering only the principal value of argument i.e (-pi,pi] we should only take 0 and pi and not -pi since it does not lies in the interval. Anyone has any idea?
Q2:
Does there exist an entire function f such that
for all positive integers n? Justify your answer.
Alright as for this, the solution is given as:
Consider
then
Now
iffTherefore if z is a zero of
, andHence g(z) has no poles in D(0,1) and so g is analytic on D(0,1).
Now
for all positive integers n and in D(0,1) with .It follows that for any analytic function f with the given property,
.However, limit of g at z=-1 does not exist implies that the limit of f at -1 does not exists and so f cannot be analytic at -1 and so f cannot be an entire function. Hence such entire function does not exist.
Well, the thing that I don't understand about this question is that since the function f is defined on positive integers n the domain and image set of f should all be positive so how could we possibly find limit of f at -1 at the very first place?
Furthermore, I don't understand why
implies that .Thanks a dozen in advance.
I think I get the idea. Thanks
Thanks!
Well, there is a corollary on Maximum Modulus Principle that goes like this:
"If
is analytic on a path connected open set and attains its maximum value at a point in , then is constant on ."Well my question are:
1.)Does this statement holds true if I replace "maximum" with "minimum"?
2.)More generally, does Maximum Modulus Principle and all its corollaries the same as Minimum Modulus Principle just that we only have to replace the word "maximum" with "minimum"?
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3.) Alright this question is not on Maximum Modulus Principle, it's something regarding the phrasing of Mathematics that I am confused in.
Let's say if we say something like
lies in is it the same as saying lies on ?and the same goes for if
lies in is it the same as saying lies on ?I am asking this because I always though if we say something lie in something such as
However, it seem to me that some textbook just use them interchangeable, could any kind soul confirm this for me?
Thanks and will appreciate if anyone could answer my questions as my exam on Complex Analysis is on next week
That it! You are the MAN! How could I have forgotten about this? Thanks a bunch.:D
Hi, may I know the degree of freedom for a chi-squared test? What is given on my notes is k-p-1 where k denote the no. of classes, p denote estimated parameter. However this is one question that really confused me:
30 passengers on a flight took part in an experiment to investigate if a new drug suppresses jet lag. The subjects were divided into two group, one given the course of treatment and the other was given a placebo.
Jet lag No jet lag
Treatment group 3 12
Placebo group 10 5
With data above, use a chi-squared test to investigate if the treatment suppressed jet lag.
Solution is given as:
There is no association between experiencing jet lag and the treatmentThe expected frequencies are as follows:
Jet lag No jet lag
Treatment group 6.5 8.5
Placebo group 6.5 8.5
Hence the test statistic is:
Degree of freedom:
My question is, why is the degree of freedom (2-1)(2-1)=1 ? Isn't it 4-1=3? since no. of classes is 4 and there are no estimated parameter?
Thanks a bunch in advance, I have an exam this week.
Thanks
could anyone confirm this for me? Thanks.
In addition what about u-v, uv, u/v? Is Laplace equation always the method to check for harmonic?
Thanks in advance.
Hi, thanks for the input bobbym and whatismath, I appreciated it.
Hi luca, thanks for replying. Anyway since it cannot be solved analytically are there other method of proofing that it is divergent?
Proof that
is divergent.I know that in order to prove such a statement you'll first need to find
and show that the limit below does not exist:However, I have difficulty integrating
at the first placeConstruct your quadrilateral with the corners marked from the top right hand side as K, all the way anti-clockwise to N. It will be much easier this way.
Hi, as my exam is round the corner, I just wish to check if my concept is right. Say if
Since if
is analytic on domain D it will means that and are both harmonic on D and hence satisfy Laplace's equation:Let
then
which also satisfy the Laplace's equation.
So
is harmonic on domain D?Oh my gosh! Think I am drunk lol
Hi Jane, thanks for correcting me. Please ignore my previous post. It's late in the night, I'll work this question again tomorrow.
Well I suspect the last line should read:
I not sure if there are simpler method but this is what I have:
Since
are the roots of and are the roots of we'll have:By expanding and comparing coefficient of both equation we'll get:
Together, we'll get:
Since
, we'll only need to prove thatBy expanding and substituting
We'll get
Which completes the proof.
Hi Ricky thanks for the info
I have to say that there are lots of helpful helper here thanks!
Hi dannyv, thanks for the effort
By the way could you elaborate what do you mean by if I write the complex logarithm it is easier?
Thanks.