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. E

    Courses What Math Course is Best Paired with Linear Algebra?

    I'm currently an applied math major. I'm creating a schedule for my next semester and I have the choice to take either complex variables or vector analysis with linear algebra and a college geometry course(elective of choice), but I don't know which pairing will be less stressful. I am currently...
  2. A

    Need to be sure of this boolean algebra problem's solution

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  3. A

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  4. Matejxx1

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  5. I

    MHB Solve Algebra Question Easily: 34

    I know that I can use guess and check, but I was wondering if there was an easier way? I got 34
  6. S

    I Solve Lie Algebra Easily: No Math Theory Needed

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  7. S

    I Lie Algebra in Particle Physics simplified

    Hello! Is there any rule to do sums and products like the one in the attached picture (Lie.png) without going through all the math theory behind? I understand the first (product) and last (sum) terms, but I am not sure I understand how you go from one to another. Thank you!
  8. Cocoleia

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  9. binbagsss

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  10. jamalkoiyess

    Linear Algebra How Does Linear Algebra Help with Differential Equations?

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  11. A

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  12. T

    Compare these two Linear Algebra courses

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  13. S

    Algebra of displacement operator

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  14. Cjosh

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  15. Rococo

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  16. caters

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  17. M

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  18. binbagsss

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  19. Rectifier

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  20. binbagsss

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  21. M

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  22. S

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  23. S

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  24. caffeinemachine

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  25. B

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  26. B

    A 3dim Poincare Algebra - isl(2,R)

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  27. KDS4

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  28. Rectifier

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  29. PhotonSSBM

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  30. Rectifier

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  31. kyphysics

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  32. NihalRi

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  33. Rectifier

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  34. MidgetDwarf

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  35. R

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  36. almarpa

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  37. J

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  38. J

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  39. binbagsss

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  40. T

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  41. D

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  42. L

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  43. M

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  44. T

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  45. N

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  46. Mikaelochi

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  47. S

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  48. S

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  49. L

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  50. N

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