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. K

    Generators of Lorentz Lie Algebra being complex?

    I was wondering about the following Λ=I+iT T are the generators and Λ a continuous LT transformation, thus it is real. Therefore T needs to be imaginary. And we can find two sets one being the generators for SO(3) J_i and the other for boosts K_i, which are both imaginary. Now I am wondering...
  2. H

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  3. E

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  4. B

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    Is the following correct? We begin with a set. Then, we specify a certain collection of subsets and thereby create a topology. This endows the set with certain properties, one of which is “nearness” and “boundedness.” Then we specify that the topology be smooth. In so doing, our topology...
  5. B

    Taking Real Analysis, Abstract Algebra, and Linear Algebra

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  6. B

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  9. H

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  10. IonizingJai

    Vector Algebra: Finding Resultant Forces at Optimal Angles | Expert Help

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  11. K

    Solving Work Problems: Algebra Techniques for Jennifer and John

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  12. G

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  13. B

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  14. E

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  15. Physics-UG

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  16. anemone

    MHB Solve Algebra Challenge: Find $\dfrac{x}{x+y}+\dfrac{y}{y+z}+\dfrac{z}{z+x}$

    If $\dfrac{(x-y)(y-z)(z-x)}{(x+y)(y+z)(z+x)}=\dfrac{2014}{2015}$, evaluate $\dfrac{x}{x+y}+\dfrac{y}{y+z}+\dfrac{z}{z+x}$.
  17. M

    Can a Projection Be an Isomorphism If It Maps to a Proper Subset?

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  18. M

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  19. C

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  20. topsquark

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  21. heff001

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  22. raay

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  23. S

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  24. Camperwes

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  25. J

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  26. G

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  27. A

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  28. anemone

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  29. L

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  30. I

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  31. AdityaDev

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  32. H

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  34. M

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  35. binbagsss

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  36. K

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  37. Duderonimous

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  38. Dethrone

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  39. P

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  41. J

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  43. K

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  44. I

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  45. P

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  46. gfd43tg

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  47. F

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  48. A

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  49. N

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  50. P

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