operation

  1. D

    Order of operation

    My daughter has a math problem that both me and my wife got incorrect due to order of operations. The problem is: (2 3/4 - 3.5) * (-2^2) Solving each term between the brackets = (11/4 - 14/4) * (4) = (-3/4) * (4) = - 12/4 = - 3. The correct answer and method according to the key is as...
  2. M

    Placing Operation Signs to Make an Equation

    Can you help me figure out this question? Place the signs +. -, and = between these digits to make an equation. You can change the order of the signs, but you must use each sign only once. 4 8 3 3 6 9
  3. Y

    Arrange Mathematical Operation Using 0-9 to Match the Post Number + 12000

    Arrange Mathematical Operation Using 0-9 to Match the Post Number + 12000 Continued from here. The rules are as given below. 1. Use the integers from 0 to 9 (one of each) to provide a mathematical expression whose value equals the post number + 12000. 2. Approximation is not allowed. 3...
  4. D

    Formula from table with operation restrictions #3

    This request is similar others of mine, but is about another topic. The similarities are that they abide by the same rules and the formula should be applied in the same system. The only significant difference will be the 3rd column of the table, from my previous requests; it may seem trivial...
  5. D

    Formula from table with operation restrictions #2

    This request is similar to another of mine, but is about another topic. The similarities are that they abide by the same rules and the formula should be applied in the same system. In the following the only difference will be the 3rd column of the table, from my previous request; it may seem...
  6. D

    Formula from table with operation restrictions

    I have a mostly automated profile/sheet/information that I'd like to automate even more as it allow custom formulas using limited data and operations. In the following table the column (col) 1 is entered (by the profile/sheet/information) then col 2 is automated and I'd like to do so for col...
  7. A

    Is the square operation in inequalities?

    5 > -5 5^2 > (-5)^2 Does one reverse the signs at this point? (Since one of the sides is multiplied by a negative?) Either way, you arrive at the contradiction: 25>25 Am I doing something wrong here, or is it illegal to square both sides of an inequality all together?
  8. B

    Check if equation defines an operation on the set of integers.

    Hi, I have the following exercise, it is required to check if the following equation defines an operation on the set of integers, and if so, check if it is associative, commutative and identity element. $m * n = mn + 1$ I have taken $m = 2, n = 3$ $2*3 = (2 \cdot 3) + 1 = 6 + 1 = 7...
  9. M

    Find the values of a so that the operation is closed in [0;1]

    I would appreciate anyone's contribution for the following exercises : 1)Find the values of a so that the operation x * y = x + y - xy - ax - ay +a is stable in the set [0;1] //// First one was solved 2) For a=0, find a formula for \overbrace{x*x*x*x* .....*x}^{n-times} .
  10. T

    algebra operation

    Can someone explain to me (step by step) how the following right hand side is obtained?$$\frac{ah^2}{n^2}\cdot \frac{n(n+1)}{2}=\frac{ah^2}{2}\cdot \left(1+\frac{1}{n}\right)$$ When i multiply the left hand side out i get:$$\frac{ah^2n^2+n}{2n^2}=\frac{ah^2+n}{2}$$ I don't get it.
  11. S

    How to calculate operation counts in linear algebra?

    i am finding difficulty in calculating operation count for Direct methods of linear systems. can some one help me finding operation count of atleast guass elemination method or dolittle method, step wise?????? :confused: :unsure:
  12. W

    Operation Order Problem

    Hi everybody! So I was going through this problem many times and my final answer was 5, but I don't know why the book insist that the right answer is 3! Here goes the problem: It'll be good if you may have a detailed solution Thanks.
  13. Mr Davis 97

    Reverse operation of exponentation

    As far as I know, in the equation b^{y}=x, log_{b}(x) = y is the "reverse" operation of exponentiation. However, in the equation b^{y}=x, why isn't b = \sqrt[y]{x} the reverse operation?
  14. M

    DFT for convolution like operation

    Let x,y be finite real valued sequences defined on 0...N-1 and let g be a non negative integer . define also on 0..N-1. In addition, the DFT of y is known in closed form. Is there a way to write z as some cyclic convolution, so that with the help of the convolution theorem z can be...
  15. U

    What kind of operation ! means

    There are couple of problems where it has 3!/ 4!, something like that i never learned ( ! ) meant
  16. L

    Identity matrix row operation problem

    please prove I(kRj)=I(Rj interchanging R1) I(kR1) I(Rj interchanging R1) where I is a n*n identity matrix, k ?F
  17. A

    Comparing two integers by (mod) operation

    Hi, I am looking to compare encrypted integers with out decrypt them. So, I am wondering if it is possible to compare two integers to determine which one is smaller than another with a specific modulus. As I know, positive and negative numbers with (mod) operation have positive reminder all...
  18. D

    groups and their operation

    why the two following subgroups which has different operation can be multiplicated together? http://p2.zhimg.com/ee/0b/ee0bc509b0f084c662cf2921acb7f58e_m.jpg
  19. R

    set operation proof

    Can someone please help me step by step to prove or disprove \bigcup(A\cup B)=\bigcup A\cup \bigcup B step by step please?... Thanks!