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. J

    Linear Algebra Which one of these Linear Algebra textbooks is the best?

    I want a good linear algebra textbook in order to learn to use linear algebra in physics but also to use it in more theoretical mathematics courses. I hope that with this poll i will also help others that want to study from a proper Linear Algebra textbook.
  2. T

    How can i solve joint proportion?

    I am currently doing aops introduction to algebra book and I can't figure out how to solve joint proportion or some ppl call it joint variation. I don't which values should i substitute for the formula, z=kxy. I don't which value should i substitute into z to the word problems. I can get through...
  3. D

    How can I succeed in Physics this time? Will it get better?

    So last semester, I withdrew from Physics with algebra and trigonometry. I am currently enrolled with another professor and I hope I excel this time in the course. He seems more attentive and friendly, along with having a noticeable passion for Physics. Today was the first day of class and...
  4. G

    Least squares problem: am I solving it correctly?

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  5. fresh_42

    Does anybody know an introduction to Lie Algebra Bundles

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  6. C

    Current Algebra: Find Current in Electric Circuit w/ 3 Resisters of R

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  7. L

    What are the elements of Lie algebra in the case of a single generator?

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  8. D

    What is the trick to properly understanding Physics?

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  9. Titan97

    Phasor algebra in AC circuit analysis

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  10. G

    Local Algebra: intersection multiplicity

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  11. Titan97

    Algebra Books for learning multinomial theorem

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  12. B

    Linear Algebra Seeking a Advanced Linear Algebra Book (Required Topics)

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  13. G

    Linear algebra: Find the span of a set

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  14. Math Amateur

    MHB Simple Notational Issue in Roman: "Advanced Linear Algebra"

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  15. barbara

    MHB Demonstrating Distributive Property of Boolean Algebra

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  16. kostoglotov

    Should I bother with this last chapter of my Linear Algebra text?

    Intro to Lin. Alg via MIT OCW 18.06 (part of Electrical Engineering), by Gilbert Strang. I've been doing it as independent study before starting my BSEE next year. I'm getting to the end. Chapter 9 is titled "Numerical Linear Algebra", and is concerned with the heavy, intricate computational...
  17. D

    Algebra, find orbits and stabilizers

    Hello I have the solution of a problem and I don't understand it 1. Homework Statement We know that every subgroup L<S10 acts on [1, 10] := {1, 2,..., 10} by the formula π • i = π(i). Consider L the subgroup of S10 generated by the permutation p = (1, 2, 3, 4)(4, 5)(8, 9, 10). Find the orbit...
  18. G

    Lie Group v Lie algebra representation

    Hi y'all, This is more of a maths question, however I'm confident there are some hardcore mathematical physicists out there amongst you. It's more of a curiosity, and I'm not sure how to address it to convince myself of an answer. I have a Lie group homomorphism \rho : G \rightarrow GL(n...
  19. D

    Representations of SU(3) Algebra

    Homework Statement I'm trying to figure out this question: "Show that the 10-dimensional representation R3,0 of A2 corresponds to a reducible representation of the LC[SU(2)] subalgebra corresponding to any root. Find the irreducible components of this representation. Does the answer depend on...
  20. aamirza

    Special Relativity -- Elastic Particle Collision Algebra

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  21. kostoglotov

    Polar and Jordan Decomp. in Intro to Linear Algebra?

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  22. T

    Linear algebra - vector spaces, bases

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  23. G

    Linear algebra: Check the statement

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  24. AliGh

    Engineering Discerete math and algebra books for programming majors

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  25. Geofleur

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  26. anemone

    MHB Proving $\sqrt[3]{a-b}+\sqrt[3]{b-c}+\sqrt[3]{c-a}\ne 0$ with 3 Real Numbers

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  27. W

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  28. N

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  29. A

    I Question in linear algebra, derivation of a certain relation

    Hello good people, please refer to this: (notice the mistake in 9.31: cos(psi) switches places with cos(phi)sin(psi) to the best of my understanding) Now, I am trying to derive 9.30 and for this, according to the book, we solve 9.32. The problem is I can not understand 9.32, the meaning of...
  30. anemone

    MHB Prove 1000th Progression of an Algebraic Series is Less than 1/79

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  31. S

    Lie group multiplication and Lie algebra commutation

    I've heard it said that the commutation relations of the generators of a Lie algebra determine the multiplication laws of the Lie group elements. I would like to prove this statement for ##SO(3)##. I know that the commutation relations are ##[J_{i},J_{j}]=i\epsilon_{ijk}J_{k}##. Can you...
  32. HaLAA

    Find the probability of a prize

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  33. D

    Definable relationships between 4 variables with 2 equations

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  34. nuuskur

    Algebra: Non-isomorphic groups

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  35. Pouyan

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  36. G

    Linear Algebra Book recommendations: Linear algebra

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  37. EternusVia

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  38. S

    Deriving the commutation relations of the so(n) Lie algebra

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  39. R

    MHB [Geometry + Algebra] Integrated Questions

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  40. ytht100

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  41. anemone

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  42. V

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  43. C

    How helpful has the "algebra" been in understanding physics?

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  44. J

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  45. R

    Find D: [(A - D)^P] / [(B - D)^R] = (C - D)^(P - R)

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  46. S

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  47. S

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  48. T

    Is it possible to learn pre-algebra to pre-calc in 9 months?

    I am currently in year 9 (9 grade for those in US) and I have a really rusty and a weak math background. I have 2 months of summer holidays coming up. I should be done with pre algebra in mid December. During my summer holidays I have more than 50 hours a week avalible for study and I was just...
  49. P

    Is ε closed under countable intersections?

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  50. Valour549

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