What is Algebra: Definition and 999 Discussions

Algebra (from Arabic: الجبر‎, romanized: al-jabr, lit. 'reunion of broken parts, bonesetting') is one of the broad areas of mathematics, together with number theory, geometry and analysis. In its most general form, algebra is the study of mathematical symbols and the rules for manipulating these symbols; it is a unifying thread of almost all of mathematics. It includes everything from elementary equation solving to the study of abstractions such as groups, rings, and fields. The more basic parts of algebra are called elementary algebra; the more abstract parts are called abstract algebra or modern algebra. Elementary algebra is generally considered to be essential for any study of mathematics, science, or engineering, as well as such applications as medicine and economics. Abstract algebra is a major area in advanced mathematics, studied primarily by professional mathematicians.
Elementary algebra differs from arithmetic in the use of abstractions, such as using letters to stand for numbers that are either unknown or allowed to take on many values. For example, in



x
+
2
=
5


{\displaystyle x+2=5}
the letter



x


{\displaystyle x}
is an unknown, but applying additive inverses can reveal its value:



x
=
3


{\displaystyle x=3}
. Algebra gives methods for writing formulas and solving equations that are much clearer and easier than the older method of writing everything out in words.
The word algebra is also used in certain specialized ways. A special kind of mathematical object in abstract algebra is called an "algebra", and the word is used, for example, in the phrases linear algebra and algebraic topology.
A mathematician who does research in algebra is called an algebraist.

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  1. Mr Davis 97

    Abstract algebra class equation

    1. The problem statement, all variables and given/known If each element of a group, G, has order which is a power of p, then the order of G is also a prime power. Homework EquationsThe Attempt at a Solution I am not sure really where to get started. I know that the class equation will be used...
  2. N

    I A new vector-product for geometric algebra?

    I am investigating the mathematical properties of a vector-product. I am wondering if it might be old-hat in GA (which is new to me)? I am using the working-title "spin-product" for a vector-product that combines RANDOM rotation-only of a direction-vector [a unit 1-vector; say...
  3. S

    Which must be first? Beginner programming, or Algebra 1?

    I am just curious about this. Must one of these be taught before the other, or does the order not really matter? Should a student be taught beginning computer programming AFTER being taught introductory algebra 1? Or can the reverse order be done? My guess is that learning Algebra 1 first is...
  4. G

    Algebra problem involving work using specific heat ratio

    NO TEMPLATE BECAUSE SUBMITTED TO NON-HOMEWORK FORUM I'm stuck on substituting the following (where gamma is the specific heat ratio): W=(P1v1 - P2v2) / (gamma-1) P1v1^gamma = P2v2^gamma substituting for v2... <= this is where I get stuck... W = [(P1v1) / (gamma-1)] * [(P2 /...
  5. M

    Taking Calc 2 and Linear Algebra at the Same Time

    I'm in a bit of a dilemma. At my university, Calc 2 is a prerequisite to Linear Algebra. However, I have been told that it's totally doable to take both at the same time. What do you guys think? Do most universities wave this requirement if you take them concurrently? Thanks!
  6. BubblesAreUs

    Algebra Textbook for Abstract Algebra / Group Theory

    I am looking for an accessible textbook in group theory. The idea here is to use it to learn basic group theory in order to take up Galois Theory. My background includes Calculus I-IV, P/Differential Equations, Discrete Mathematics including some graph theory, Linear algebra, and am currently...
  7. M

    Is financial engineering my answer to solving complex financial problems?

    Hi guys, Am I totally lost if I am searching for help in financial engineering here- I have been struggling with a question for way too long now. Thanks,
  8. JuanC97

    I Understanding Co-vectors to Dual Spaces and Linear Functionals

    Hi, I'm trying to get a deeper understanding of some concepts required for my next semesters but, sadly, I've found there are lots of things that are quite similar to me and they are called with different names in multiple fields of mathematics so I'm getting confused rapidly and I'd appreciate...
  9. M

    MHB Algebra Word Problem: Investment Amounts

    Not sure how to start this one: Yolanda invests \$6000. Some of the money is invested in stocks paying 6% a year and some in bonds paying 11% per year. She receives a total of \$580 each year from these investments. How much money is invested in stocks and how much money in bonds?
  10. K

    Can I take AP Physics 1 while concurrently taking Algebra 2?

    Next year, I want to take AP Physics 1 but I am worried that it would be confusing since I would still be learning about Algebra 2. Is it recommended to do this?
  11. J

    Wavelength and Frequency in a Waveguide

    The problem states that the wavelength and frequency in a waveguide are related by: ##\lambda = \frac{c}{\sqrt{f^2 - f_0^2}}## then asks to express the group velocity ##v_g## in terms of c and the phase velocity ##v_p = \lambda f## Solution: Given that ##\omega = 2\pi f##, ## \omega(k) =...
  12. HajarB

    Algebra A Course in Algebra Book Study Group | Self-Learning Support

    Hey everyone, I'm currently studying A Course in Algebra by E.B. Vinberg, and I was wondering if anyone is studying the same book. I think it will be a less lonely journey for all of us self learners if we can form a book study group to discuss ideas and exercises.
  13. C

    Linear Algebra - Finding coordinates of a set

    Homework Statement Find the coordinates of each member of set S relative to B. B = {1, cos(x), cos2(x), cos3(x), cos4(x), cos5(x)} S = {1, cos(x), cos(2x), cos(3x), cos(4x), cos(5x)} I am to do this using Mathematica software. Each spanning equation will need to be sampled at six separate...
  14. B

    Algebra Supplementary Problems for Zariski/Samuel's Commutative Alg.

    Dear teachers, I am curious if you know some good books that have problems well supplemented to "Commutative Algebra I-II" by Zariski/Samuel. I am really enjoying it, but it does not have any exercise, leaving me to try coming up with my own problems (it is fun to do, but I would like to solve...
  15. T

    MHB Linear Algebra Conditions: Solving for ab≠1

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  16. T

    I Linear Algebra Conditions: Solving for ab ≠ 1

    http://imgur.com/a/xIydC The answers is b) ab≠1, but I have no clue how to get to that answer... Can someone help me? :D
  17. M

    Linear Algebra: Matlab Question

    I am taking a linear algebra class, and it has a required lab associated with it. Here is the following problem that I must solve using Matlab 1. Homework Statement Write a function using row reduction to find the inverse for any given 2x2 matrix. Name your function your initial + inv(M), the...
  18. B

    Algebra Tips for reading Grothendieck's EGA/SGA/FGA trilogy

    Dear Physics Forum advisers, I am very interested in studying the art of algebraic geometry, motivated by its applications in the machine learning and data analytics. I recently came across Grothendieck's EGA/SGA/FGA saga, and I am really interested in reading it as I like how it presents the...
  19. arivero

    I Bootstraping a space from its tensor square

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  20. Kara386

    Find the Lie algebra corresponding to this Lie group

    Homework Statement The group ##G = \{ a\in M_n (C) | aSa^{\dagger} =S\}## is a Lie group where ##S\in M_n (C)##. Find the corresponding Lie algebra. Homework EquationsThe Attempt at a Solution As far as I've been told the way to find these things is to set ##a = exp(tA)##, so...
  21. Kara386

    How Is the Dimension of su(n) Calculated?

    Homework Statement Show the (real) dimension of su(n) is ##n^2-1##. Homework EquationsThe Attempt at a Solution ##su(n) = \{ A \in M_n(\mathbb{C}) | A+A^T = 0, tr(A) =0 \}## Maybe the solution is obvious, because I can't find a thing online about how to do this. But I can't see how to do it! I...
  22. binbagsss

    GR algebra pretty much (weak limit thm)

    Homework Statement Hi I am stuck on a small algebra set in the weak limit theorem to recover Newtonian equations The text I am looking at: ##\frac{d^2x^i}{ds^2}+\Gamma^i_{tt}\frac{dt}{ds}\frac{dt}{ds}=0## (1) ##\Gamma^{i}_{tt}=-1/2 \eta^{ij}\partial_{j}h_{tt} ## (to first oder in the...
  23. Q

    Simple Algebra problem, but done with reference frames

    Homework Statement Sonia walks up an escalator which is going up. When she walks at one step per second, it takes her 20 steps to get to the top. If she walks at two steps per second, it takes her 32 steps to get to the top. She never skips over any steps. How many steps does the escalator...
  24. michaelgtozer

    I 1st year linear algebra question

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  25. O

    I Why is stress considered a tensor?

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  26. Adgorn

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  27. Charles Henderson

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  28. V

    I Linear algebra ( symmetric matrix)

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  29. CynicusRex

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  30. W

    Show: Elementary row operations don't affect solution sets

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  31. C

    Complex Conjugates in Quadratic Equations: Solving for z

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  32. CynicusRex

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  33. UsableThought

    Gelfand's "Algebra" prob. 42 - corrections & hints?

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  34. CynicusRex

    Prove that if a² + ab + b² = 0 then a = 0 and b = 0

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  35. Hypercube

    Linear Algebra / Linear Maps (Transformations)

    This isn't really a homework question, I just need help understanding the example: ===================== ==================== So transformation takes complex n-tuple as input, and it seems output is also a complex n-tuple (which is what makes it "operator"). But permutations of n entries is...
  36. Xico Sim

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  37. binbagsss

    I Modular form quick question translation algebra

    Please see attached. I am trying to show that ## T_{p} f (\tau + 1) = T_{p} f (\tau ) ## ##f(\tau) \in M_k ## and so can be written as a expansion as ##f(\tau)=\sum\limits^{\infty}_{0}a_{n}e^{2 \pi i n \tau } ## ##f(\tau + 1) = f(\tau) ## since ##e^{2\pi i n} = 1## Similarly ##f(p\tau + p) =...
  38. Milsomonk

    I Geometric Algebra formulation of Quantum Mechanics

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  39. CynicusRex

    B Factoring trick by determining a zero value

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  40. F

    Foundations I have complied a list of textbooks about Trig, Algebra, Etc

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  41. Derek Hart

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  42. K

    Solving Algebraic Expression with Limits

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  43. caters

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  44. Math Amateur

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  45. Math Amateur

    I Centre of an Algebra .... and Central Algebras ....

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  46. binbagsss

    I QFT Feynman Propagator Algebra

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  47. Unteroffizier

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  48. binbagsss

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  49. MrsM

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  50. Math Amateur

    MHB Books on Noncommutative Algebra

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