Homework Statement
The question is attachedk
Homework Equations
Sn = n/2[2a+(n-1)d]
Sn = (a x (1-r^n))/1-r
The Attempt at a Solution
I already found the general formulas:
Tortoise:
Sn = n/2(40)
Hare:
Sn = (1000 x [1-0.5^n])/0.5
And I know that there tortoise will finish the...
Homework Statement
For every x in Z and for every natural number n if:
x^{2}\equiv1(mod47)\Rightarrow x^{n}\equiv1(mod47)orx^{n}\equiv46(mod47)
The Attempt at a Solution
Alright I said since 47 is prime and relatively prime with x then by fermat's little theorem we will get...
I suppose the title should be "Matrix polynomial T or F" but whatever.
Homework Statement
True or false: if A2-2A+I=0, then A-1=2I2-I
The Attempt at a Solution
My thought:
A2-2A+I=0 becomes (A-I)(A-I)=0
so
A = I
The inverse of I is I.
So the second equation:
A-1=2I2-I
becomes
I = 2I2-I...
Hi all, newbie here.
So I've tried asking this question on Reddit with barely a reply and now another forum I frequent with also not much of a reply. And a while back an acquaintance recommended this forum to me.
So my request is can you recommend me some mathematics textbooks that go from...
Homework Statement
Homework Equations
a. I know that x*a mod y should be the same as y*b mod x but I don't understand why
b. I know that an inverse can be constructed because x and y are mutually prime and gcd(x,y) = 1 , but I have no clue at what pair x and m is possible
c. I have no idea...
Homework Statement
Let a_{n} be an alternating series whose terms are decreasing in magnitude. How to compute the sum as precisely as possible using four-digit chopping arithmetic? In particular, apply the method to compute \sum\limits_{n = 0}^\infty {\frac{{{{( - 1)}^n}}}{{(2n)!}}} and...
Hey! I have this: 2(√(1-a^2 ))+ 2a
How to determine the maximum value of this?
I think good for this is Inequality of arithmetic and geometric means, but I don't know how use this, because I don't calculate with this yet.
So, have you got any ideas?
Poor Czech Numeriprimi... If you...
Good Day,
My friends and I are stuck on solving the last part of the attached problem.
The solution is 2^[(n^2 + n)/2] - 1.
Can anyone help us with solving this?
Thanks & Regards,
Nicodemus
https://www.youtube.com/watch?v=uIjMIo8Lsrw
Do I have this right? It sounds like the people who didn't do so well on the PSAT, who used their right brain, "overthought" the simple arithmetic problems, by using the (subjective?) quantity-related part of their brain. the students who did...
Homework Statement
Sum of first three members of increasing arithmetic progression is 30 and sum of their squares is 692. What is the sum of the first 15 members?The Attempt at a Solution
So i have system of equations:
a1 + a2 + a3 = 30
(a1)^2 + (a2^2) + (a3^2) = 692...
Homework Statement
Let a_{m+n}=A and a_{m-n}=B be members of arithmetic progression then a_{m} and a_{n} are? (m>n).The Attempt at a Solution
I fugured that a_{m}=\frac{A+B}{2} but i have no idea what a_{n} is.
In my textbook solution is a_{n}=\frac{(2n-m)A + mB}{2}
How did they arrived to...
Is it true that if A \equiv B \mod{\varphi(N)} where \varphi (N) is Euler's totient function then a^A \equiv a^B \mod{N}?
I'm not after a proof or anything but I didn't do a number theory course and it seems that this fact is used in many questions I'm currently doing.
A Newton is: ( (one kilogram times one meter) per second) per second)
I am trying to get at the basic logic of how we can apply numbers to reality.
I have a good understanding of how we use a ratio to express things. A ratio separates one quantity into the amount of another quantity. In fact...
Homework Statement
A textbook of mine asserts that ℝ is a subset of ℂ. The motivation for this is drawn by defining complex addition and multiplication and then showing that these operations on complex numbers of the form (x,0), with x an element of ℝ, are isomorphic to the field ℝ witih...
Homework Statement
Given that a2, b2 and c 2 are in arithmetic progression show that:
$$\frac{1}{b+c} , \frac{1}{c+a} , \frac{1}{a+b} $$
,are also in arthimetic progression.
Homework Equations
The Attempt at a Solution
So I assume by "in arithmetic progression" they mean those...
Homework Statement
Execute the arithmetic operations using 6-bit binary numbers in 2's complement representation.
18+11
(just going to list this first task)
Homework Equations
To convert from regular binary number, from LSB, do not invert initial o's, or first 1, but invert all other...
I decided to try some of the problems in my Mechanics text without a calculator to see how well I could approximate the answers using differential equations and mental arithmetic. I was a bit slow, but I remembered some tricks I used as a kid in grade school that I hadn't used in ages. Does...
(This is my first post.)
I can't seem to find a good way of solving this sort of congruence for x:
x^2 / 3 + 11 \equiv 5 (mod x)
Through trial and error it appears at least 3 and 6 are answers, but how can you reach them regularly? (I'm heard conflicting things about fractions being...
Homework Statement
In an arithmetic sequence, the 11th term is 53 and the sum ofof the 5th and 7th terms is 56. Find the first 3 terms of the sequence.
Homework Equations
The Attempt at a Solution
I'm trying to use the formula: tn= t1+(n-1)d but don't have right numbers. please...
Find the sum of \Sigma 200 r=5 5r-2
Sn = n/2 [2a + (n-1)d ]I used S 200 and I got about 101400 but then when I verified on my calculator it was 100058, my calculator has the sigma notation for working out the sum of , how do you get 100058?
I came across a problem like this (not homework)
x^2+y^2-k
For example,
x^2+y^2-24 \text{ ,n=4}
x^2+y^2-45 \text{ ,n=8}
If x and y are any positive integers (not given) and k is a positive integer (given), is this expression divisible by n (a positive integer that is given). A...
Homework Statement
If four distinct points on the curve y=2x^4+7x^3+3x-5 are collinear, then find the arithmetic mean of x-coordinates of the aforesaid points.
Homework Equations
The Attempt at a Solution
I think that the four points mentioned must be the roots of the equation.
If one is solving a modular equation:
4k \equiv 1 \: (\text{mod } n)
with n even, known, for k, then one needs to find the inverse of 4 modulo n:
4x - 1 = nc
4x - nc = 1
But this only has solutions iif (4,n) = 2 (n is even, but not a multiple of 4), which doesn't divide 1, so...
Homework Statement
If k is an integer, explain why 5k +2 cannot be a perfect square.
Homework Equations
n/a
The Attempt at a Solution
I'm in way over my head and not really sure what type of proof I should be using. In my course, we just went over some number theory and modular algebra so...
Use a geometric or algebraic argument to find a formula for the partial sums $A_n$ of an arithmetic sequence.
I know that the partial sum is $S_n = n/2(2a_1+(n-1)d)$ where d is the difference.
$A_n = \sum\limits_{k = 1}^n a_k$
I can come up with $n/2(a_1+a_n)$ but how do I get the difference?
"Determine the least possible value of the largest term in an arithmetic progression of seven distinct primes."
I really have no clue what to do here. Is there a general tactic that you can use to do this, other than trial and error? Some experimenting gives you these of arithmetic...
Mathematica agrees with my second solution (not the first one though). The back of my textbook says: "\sqrt[4]{8}[\cos(\frac{5\pi}{8}) + i\sin(\frac{5\pi}{8})] and \sqrt[4]{8}[\cos(\frac{13\pi}{8}) + i\sin(\frac{13\pi}{8})]"
Edit: The second z in my picture should be |z|, the modulus...
when i do higher maths i make a tone of basic algebra and arithmetic mistakes. i was going a basic AX = B using LU decomposition in linear algebra and I had to go back and check my basic math about 6 times before i got the right answer. is it just me or do a lot of people do this?
Basically I'm writing my MSc dissertation right now, and I've been doing a lot on primes
I've written all my code in MATLAB, but my supervisor told me today that MATLAB is crap for higher order arithmetic and the primes only go up to something like 10 digits long.
SO I'm kinda screwed...
Homework Statement
Hi everyone! I have a homework question given below:
One scheme of pseudorandom number generator is the linear congruential generator where we pick some modulus m, constant a and b and a seed x0, then generate sequence x1, x2, x3, ... according to the equation:
x(t+1) =...
Homework Statement
Hi everyone, I have a problem in the following modular arithmetic operation
1/2*(x-4)(x-5) = 4(x-4)(x-5) (mod 7) ("=" means congruent in this expression)
Homework Equations
The Attempt at a Solution
I am completely lost on how the operation is valid. If...
I just came up with a problem I hope you will find interesting, but I can't seem it solve it myself. I thought of induction as some guide, but am not sure how to proceed.
There are N terms in some finite arithmetic progression. Two of those terms are equal to 3. Prove that all terms in this...
Homework Statement
For which values of n≥2 does the implication:
axb=0 ⇔ a=0 or b=0
For some Zn (n should be a subscript)
NOTE: For the a x b, the x should be the x that has a circle around it. I didn't see that symbol in the "quick symbols" :)
Homework Equations
I know that this...
1. Write out in full and determine the sum of the finite arithmetic series
r = 9
Ʃ 5r 5,10,15,20,25,30,35,40 <-- until 9
r=1
But how do I determine the sum of the finite arithmetic series? I forget the formula :/
Homework Statement
Different numbers x, y and z are the first three terms of a geometric progression with common ratio r, and also the first, second and fourth terms of an arithmetic progression.
a. Find the value of r.
b. Find which term of the arithmetic progression will next be equal to...
Hello,
The formulation of the question says:
Show, using congruences and disjunction of cases, which,for all natural n є Ninteger, the integern (n+1) (2n+1) is a multiple of 6.
Simultaneously, themultiple of 3 is a multiple of 2 (number), then it is divisible by 6
3 cases are...
Homework Statement
Prove that it is impossible to find an integer n, such that
n^2 = 2 mod(4) or n^2 = 3 mod(4)
Hence or otherwise, prove that there do not exist integers m and n such that
3m^2 - 1 = n^2
Homework Equations
The Attempt at a Solution
Since n must be...
Homework Statement
Solve in K=\mathbb{Z}/_{5}\mathbb{Z}\cdot\mathbb{Z}/_{5}\mathbb{Z} the following system of equations:
\begin{cases}
2^{-}x-3^{-}y=1^{-} & 1^{-}x+2^{-}y=2^{-}\end{cases}
Not that the ^- means a number with a bar over it. ( I don't know how to input it in the latex software...
Hi,
I have the following equation:
\gamma=\frac{1}{\frac{1}{N}\sum_{n=1}^N|\lambda_n|^{-2}}
where lambdas are the eigenvalues of an N-by-N circulant matrix A.
I used two properties to bound the above equation...
Chinese remainder theorem help
Homework Statement
Solve in Z^{2}:6x-5y=1
Conclude the solution to the system:
X≡2(mod5) , X≡1(mod6)
The Attempt at a Solution
1- solved the equation and found one unique solution which was S={(1,1)}
Given:
X≡2(mod5) , X≡1(mod6)
X≡2(mod5) means X=5t+2...
The proof says that -
Let,
Sn= a+(a+d)+(a+2d)+...+(a+(n-2)d)+(a+(n-1)d)----->1
Sn= (a+(n-2)d)+(a+(n-1)d)+...+a+(a+d)+(a+2d)------>2
Now if we have to add such things(1 and 2) how would we do that?
So we're doing modular arithmetic in my proof class. I have a weird cycle when learning something new in pure math, I think "wow, this is just exceedingly indepth version of something learned by gradeschool children." Then I find something (on my own, not in the textbook, just thinking about it...
Problem: Show that for each k, the function σk(n)=Ʃd|n dk is multiplicative.
The attempt at a solution:
What I know is that I am supposed to use the Lemma which states that if g is a multiplicative function and f(n)=Ʃd|n g(d) for all n, then f is multiplicative. I am just very confused...