1. I

    solve system of equations using row operations on augmented matrix

    Hey guys I really need some help on solving 2 algebra problems. The question states: Solve the system of equations using row operations on the augmented matrix. Problem 1. x+y-z=5 x+2y-3z=9 x-y+3z=3 Problem 2...
  2. F

    Solving a system using elementary row operations

    If someone could please help me with this. its a question about Solving a system using elementary row operations which is honestly one of the easiest and msot simple things to do but for the life of me I cannt understand what I am doing wrong (Headbang) I solved the system so i know what hte...
  3. B

    set operations

    hi, can anyone show me why is this true: P(\cap_{i=1}^{n}E_{i}) \leq P(\cup_{i=1}^{n}E_{i}) P is a probability function thank you
  4. S

    Proof of interesting equation: Related Topics, groups, semigroups, binary operations

    Here is the question: "Let G= Z x Q (Where Z is the set of integers and Q is the set of rational numbers) and define a binary operation o by (a,b) o (c,d) = (a+c,2-cb+d) - (*) Is (G,o) (i) a semigroup, (ii) a group? You must give full reasoning for...
  5. M

    Operations with Algebraic Vectors

    The question that I am having trouble with is: a) Find the point on the y-axis that is equidistant from the points (2,-1,1) and (0,1,3). b) Find a point not on the y-axis that is equidistant from the points (2,-1,1) and (0,1,3). I'm unsure of where to even start, so if anyone can give me any...
  6. M

    Simple Question Regarding Order of Operations

    Order of Operations 2(−4)2 + (6)(−4) − (−8) = 16 Why does this expression not equal -48? Should not it simplify to: = -16 * 2 + (-24) + 8 = -32 -16 = -48 To my understanding, I am following the PEMDAS process to achieve -48; alas, my calculator disagrees. It would seem that perhaps either the...
  7. C

    Neutral Operations

    If we neutralize the operations of ADDITION and MULTIPLICATION, we arrive at a set -- let's call it it a subset of the "Neutral Set." FOR EXAMPLE, LET A+B = A*B = C .... THEN THE OPERATIONS OF ADDITION AND MULTIPLICATION ARE HELD NEUTRAL TO EACH OTHER. WE CAN SOLVE THIS EQUATION: A+B-B = AB-B A...
  8. D

    Operations analysis word problem

    Hi all, I haven't taken a math class in years and am having a great deal of trouble. I got this problem from a professor and need help approaching it (basically, I haven't the slightest clue). Anything you guys are willing to do to advise, I would really appreciate it. Thank you so much in...
  9. S

    binary operations, commutative / associative

    Deleted DELETED Sorry
  10. D

    Binary Operations and Equivalence

    Hi I have this question and have no idea how to go about it. Any help would be greatly appreciated.
  11. H

    Analysis of algorithm

    Can some one tell me if i am doing i right a function 23n^2 operation for input size n. 1) how many operation per second would your computer have to do in order to complete an input size 100 in 10 minutes ? 2) Assume the computer does 50000 operation in a second. what is the largest amount...
  12. M

    Order of operations clarification

    Hello all! I am a new member of this forum, and am eager to partake in many wonderful math discussions and offer as much help as I can! My first post, however, is a bit of an embarrassing confession (especially considering I enjoy math so much that I teach it at the high school level)! I have...
  13. X

    How to find if neutral/idnty element exists for 16 different binary operations of *?

    Suppose I'm given an operation * on a set A\,\, \text{where}\,\, a,b \in A such that the operation between two elements of set A is also an element of set A Now there are 2 \times 2 \times 2 \times 2 = 16 possible binary operations of * on set A. If I'm asked to find if there exists a...
  14. C

    Operations Management problem

    A supermarket buys cabbage each day to ensure fresh produce. Each morning cabbage that is left from the previous day is sold to a dealer who resells it to farmers as animal feed. This week the supermarket can buy fresh cabbage for 40 rupees a box and sell it for 100 rupees a box. Old cabbage is...
  15. E

    Determinants (using elementary row operations)

    Hi, if anyone could explain how you get from (x+y+z+t)det 1 1 1 1 qqqqqqqqqqq y z t x qqqqqqqqqqq z t x y qqqqqqqqqqq t x y z to (x+y+z+t)det 0 1 1 1 qqqqqqqqqq (y-z+t-x) z t x qqqqqqqqqq (z-t+x-y) t x y qqqqqqqqqq (t-x+y-z) x y z that would be brilliant! Totally...
  16. Tclack

    prove elementary row operations

    the one where you can switch them is understandable, the one where you can multiply through by a constant is easy, but the one where you add the multiple of one row to another row to get a new row is weird. I've found that it's similar to solving linear equations by adding them together ex 3x...
  17. S

    Just a simple order of operations question

    if I have 4 + ((a - 1) / 12) = 24 Why can I not move the 12 over to the other side first? Making it 4 + a - 1 = 24 * 12 Howecome I have to move the 4 over first? I never really knew why, possibly there is an order to moving things over the = sign? Thanks for any help.
  18. K

    symbols as operations

    the question is as follows: For all numbers x and y, let the operation ■ be defined by x ■ y = xy-y. If a and b are positive integers, which of the following can be equal to zero? I. a■b II. (a+b)■b III. a■(a+b) does one distribute choices II and III to a■b + b■b and a■a + a■b respectively...
  19. A

    What is M in terms of a single number? (Order of mathematical operations)

    These two problems are about the order of mathematical operations, something we didn't cover in my high school maths course. I hope someone is willing to explain it to me! Solve the following problems without a calculator: 1. Given the following equation, what is M in terms of a single...
  20. D

    Quick order of operations question

    When I have: -(x + 1)^2 = 4 Do I take the square root of -(x + 1) or (x + 1)? Also, am I doing this question properly?