Homework Statement
if z = 1/sqrt 2 + i/sqrt2
Homework Equations
show that z + z4n+1 = 0,
when n is any odd integer.
if n is an even integer, find z + z4n+1 in rectangular form.
The Attempt at a Solution
I have no clue where to start...
the integer part is ... (?? distributive ??)
Homework Statement
Define the floor of a real number k where [k] is the least smallest integer from k.
I want to show that [a - b] = [a] - [b]
Homework Equations
n/a
The Attempt at a Solution
[1.2 - 5.7] = [-3.8] = -4
[1.2] - [5.7]...
Homework Statement
switch statements. y is an integer number. Use a switch statement to set B equal to one of the following values: true, false, or the vector [1 0 1]. If y is {1,2,3,5,7}, then set B to true. If y is {4, 6, 8, 10}, then set B to false. If y is neither, then set B to the...
Homework Statement
A is an invertible integer matrix. Prove that if det A = 1 or det A = -1, then the inverse of A is also an integer matrix.
Also prove the reverse, if A-inverse is an integer matrix then its determinant is 1 or -1.
Homework Equations
I'm not too sure how to start...
Why 30 is the largest integer such that none of its...?
Why 30 is the largest integer such that none of its totatives are composite?
which means All the coprime numbers that below 30 are primes..
30=> 7,11,13,17,19,23,29
?//
and if you have a proof that it is the biggest integer please Help...
Homework Statement
Prove that the expression \frac{a(a^2 + a)}{3} is an integer for all integers \geq 1
Homework Equations
The Attempt at a Solution
a(a^2 + a ) = 3q + r
r can be:
r = 0,1,2
for r = 0
\frac{a(a^2 + a)}{3} = q
q is an integer by the division algorithm.
When I...
ABCDEFGF is an 8-digit positive decimal integer, where each letter represents a different decimal digit from 0 to 9. The digits 1 and 9 do not appear. The nonzero even digits appear in ascending order, and the odd digits appear in descending order in ABCDEFGF. None of A and E can be zero...
Determine a 9-digit positive integer that uses each of the decimal digits from 1 to 9 exactly once, such that:
(i) The sum of the digits 1 and 2 and all the digits between them is 9.
(ii) The sum of the digits 2 and 3 and all the digits between them is 20.
(iii) The sum of the digits 3...
so I have to prove that a^3-2b^3-4c^3 = 0 has no positive integer solutions. I have gotten through most of the proof but now I am stuck, and if you guys could give me a nudge in the right direction that would be great.
work done so far:
proof by contradiction, i assumed that...
Homework Statement
show that every positive integer can be written as the product of a square and a square-free integer (an integer that is not divisible by any perfect squares other than one
The Attempt at a Solution
well i can see by example that this works: i.e 60=22*3*5...
Homework Statement
Find the largest positive integer n such that n^3 + 100 is divisible by n + 10.
Homework Equations
The Attempt at a Solution
The hint I've been given is to use (mod n + 10) to get rid of the n.
but i don't quite see how it would work :S
all my attempts...
Can someone explain why if an invertible matrix A has det = 1 and all integer entries, its inverse also has all integer entries? det(A) = 1 means that if you apply the big formula (permutations) the sums of the entries add up to 1. But what does that have to with having integers in its...
For example a number whose domain would be all positive would be described as a number k, where k > 0.
How would you describe a number that is an integer, ie not 1.4, 7.666 et cetera. I can't think of a way to define this mathematically (or a way that includes any number of digits). I know...
Like for example
Prompting message reads.
"Please enter a positive value"
Example:
Please enter a positive value: 234.7
Rounded to the nearest integer the number is: 235
Please enter a positive value: 10.3
Rounded to the nearest integer the number is: 10
What I have...
Homework Statement
Use proof by contradiction to show that every integer greater than 11 is a sum of two composite numbers.
The Attempt at a Solution
The question sounds a bit awkward for me since for the numbers I have tested so far. The number can be consists of 1 prime 1 composite or...
I was given this homework today and without much explanation from the teacher , I can't find anything similar in my book,
1.- [[ x]] = [[y]] find outside domain/range , argue inclusion or exclusion
2.- compare and contrast (1) y=[[2x]] (2) y=2[[x]] (3) y= [[x/2]]
3.- state domain and...
Dear all,
I have a problem with Fortran 90. I want to declare an integer which is enable to support till numbers such as Avogadro number (6.022*10**23). I use "Microsoft Fortran PowerStation 4.0". Can anyone can help me please?
Regards,
I have a doubt about electric flux.
It is said to be the no. of field lines passing through a given area.
But then we integrate it as:
\int\vec{E}.\vec{ds}=\Phi
However, bein the number of field lines does it not have to be an integer?
I am posting an integer factorization algorithm that I have developed. I am hoping for feedback on any obvious flaws that I might have missed before writing a computer programme to test it out.
Thanks in advance
Visu
Homework Statement
Hi, I hope someone could help me, I have been trying to solve this problem with FFT in matlab, why?, because my teacher gave it as homework. The problem is the following.
Obtain the value of the following integer using FFT:
Homework Equations
the integer goes...
Hi, I hope someone could help me, I have been trying to solve this problem with FFT in matlab, why?, because my teacher gave it as homework. The problem is the following.
Obtain the value of the following integer using FFT:
the integer goes from [-infinte, infinite], and the function is...
we must obtain 'N' and a(i) i=1,2,3,....,N on condition that
the product a(1)a(2)a(3)...a(N) is the highest possible
a(1)+a(2)+a(3)+...+a(N)=73
every a(i) is positive
here N (this is the hardest part) is not known and must be calculated
[SOLVED] A limit
Homework Statement
How do you show that
\lim_{x\rightarrow a}\frac{e^{-a^2/(a^2-x^2)}}{(a^2-x^2)^{2m}(x-a)}=0
for 'm' a positive integer and 'a' a real number >0??This is a type 0/0 indeterminate form but l'Hospital's rule is not helpful because when you differentiate the...
Homework Statement
Prove that for all x there exists and x if it is an element of the positive integers, then there is an integer y and an integer z.
Homework Equations
The Attempt at a Solution
I know that the contrapositive would be "If there is not an element of the positive...
Homework Statement
Can someone explain the notation of the integer ring(Z)? My friend's in Math 100 and has questions on Z. I have never heard of ring's before and I'm at a loss to help him. From what I've gathered Z is a set of all integers. They ask for the invertible elements in different...
Homework Statement
I don't know where to start on this question - could someone please point me in the right direction so i can look up the method.
Q: Find integers x, y such that 45x + 63y = 99. Can we find integers s, t such that 45s +65t = 80? Either find them or prove they cannot exist.
Homework Statement
Prove that the square of any integer a is either of the form 3k or of the form 3k+1 for some integer k.Homework Equations
The Division Algorithm: Let a,b be integers with b>0. Then there exists unique integers q and r such that a = bq + r and 0<=r<bThe Attempt at a Solution...
Could anyone please answer this
You are confronted with the following formula:
A * [(B + C)(D - E) - F(G*H) ] / J = 10
Knowing that each variable is a unique, single-digit, nonzero number, and that C - B = 1, and H - G = 3, what is the number ABCDEFGHJ, where each letter is a digit...
how does one go about finding integer solutions for an equation such as this? Is it easier to merely find how many solutions?
y^2 = x^3 + n, n is some integer.
This is a problem from Terence Tao's book, and I cannot locate the solution anywhere, so I thought I'd post it here.
1. Homework Statement
X^4+131=3y^4, Show that the equation has no solutions when x and y are integers.
Homework Equations
None? Not sure.
The Attempt at a...
Homework Statement
How would you prove using number theory that C(n,m) is an integer where n => m =>1? Do you need the Chinese Remainder Theorem? It seems like it should follow easily from what C(n,m) represents but it is hard for me for some reason.
Homework Equations
The Attempt...
one of the "maths challenge" questions. one of the only ones i couldn't do :S I've tried for a good number of hours, but havnt found a way to do it. I feel any more time would just be brute forcing it which i wouldn't have time for in the exam anyways.
hope you can help
Homework Statement...
Homework Statement
I need the eigenvalues of [[3, -1][-1, 1]] (ie [[row1][row2]])
The Attempt at a Solution
A-xI = [[3-x, -1][-1, 1-x]]
so I get the characteristic polynomial x^2-4x+2=0 from det(A-xI)=0
Is this correct? Because I won't get integer eigenvalues from it
Homework Statement
Let n and k be positive integers. Show that k^{1/n} is either a positive integer or an irrational number.
The Attempt at a Solution
I set q = k^{1/n}. Then I set q = \frac{m}{p} . (Where m and p don't have common factors.) Then m^n = k * p^n . So then k is a factor...
"Reflection of an Integer"
I haven't encountered this before. I'm not sure how to approach it. At this point it's not even clear to me why the result should only be divisible by one number in *every* case.
The reflection of a positive integer is obtained by reversing its
digits. For...
Homework Statement
Is it there a method to find out if a polynomial has no integer roots?
The Attempt at a Solution
I tried the division of polynomials, as well as the Horner's Method, but no luck.
Hi,.. using a Sturm or other sequence, could we find how many integer roots have the Polynomial
K(x)= \sum_{n=0}^{d} a_{n}x^{n}
where all the 'a_n' are integers (either positive or negative)
Let be a open curve on R^2 so x^{n}-c-ky=0 where k,n and c are integers, are there any methods to calculate or at least know if the curve above will have integer roots (a,b) so a^{n}-c-kb=0 ?? or perhaps to calculate the number of solutions as a sum (involving floor function) over integers of...
Why are the atomic weights of elements not integers and how many grams would there be in 1 amu (atomic mass unit) of a material?
I know these are trivial questions but it's been a long time since I left school!
Thanks.
-SK
Is there a quick way to find integer values of x that give integer values for y?
(x^2-R)/(P-2x)=y
sqrt(R) rounded down<x<P/2
an equivalent equation is
x^2+Px+R=y y= a perfect square
sqrt(x^2+Px+R)= integer
P and R are integer values. They are very large...
Homework Statement
Prove that if m is a positive rational number, then:
m + 1/m = integer
Only when m = 1
Homework Equations
Don't know any
The Attempt at a Solution
That's the problem, I don't know where to start. I have tryed a few things, but none of them works out for...
The other day, Mack was preparing a table consisting of integer Fahrenheit temperatures (F) which yields integer Celsius (C) equivalent upon conversion.
He noted that F= 527 gave the corresponding C value as 275 and realized that, he could have simply moved the first digit in F to the end to...
hi guys..
Does this statement require a proof? It seems pretty obvious to me.
"prove that there is no integer between n and n+1 where n is an integer."
Also if it does require a proof, what I need to show? Just few hints will suffice.
thanks
jitendra