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. awholenumber

    Looking for practice problems for algebra

    Can someone recommend me some books that have practice problems for algebra with answers ?
  2. H

    Find the max and min value from equation?

    Homework Statement Homework Equations f ' (x) = 0 --> to find extreme points The Attempt at a Solution ## 2x^2 + y^2 = 4## ## y = \sqrt{4 - 2x^2}## ## y ' = \frac {-2x} {\sqrt{4-2x^2}} ## ## 0 = \frac {-2x} {\sqrt{4-2x^2}} ## x = 0 also ## 4 - 2x^2 >= 0 ## ## 4 >= 2x^2 ## ## \sqrt{2} >= x...
  3. H

    Find the min and max value from absolute function?

    Homework Statement Homework Equations f ' (x) = 0 -> to find extreme pointThe Attempt at a Solution can I differentiate the function directly? f ' (x) = |1| + | 2x - 2| 0 = 2x - 1 x = 1/2 and x from domain = { 0, 2 } the range we get : f(0) = 1 f(2) = 1 f(1/2) = 1/2 + 3/4 = 5/4 min = 1 max...
  4. H

    How to find chords, intersections of chords on circle?

    Homework Statement Homework EquationsThe Attempt at a Solution this is the answer https://www.algebra.com/algebra/homework/Circles/Circles.faq.question.1038060.html but why the c1 = 0, c2 = 1, c3 = 3, c4 = 6 etc why not c2 = 2? c4 = 4?
  5. O

    Courses Linear Algebra vs Deterministic Operations Research for CS

    Hey all, I'm currently working on my CS degree with a mathematics minor. After this Fall, I will only have one more course to take to finish my minor. I'm debating between Linear Algebra and Deterministic Operations Research. I do have other options, but these seem to be most applicable to CS...
  6. H

    Find the total number of subtraction remaining 1111?

    Homework Statement Homework EquationsThe Attempt at a Solution 5 digits minus 4 digit remaining 11111? if the 5 digit = 20000 and the 4 digit = 8889 so remaining 11111 digits 1 to 9 have been used? what am I supposed to do?
  7. H

    Log inside log -- find the x in its max domains?

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  8. Elroy

    Linear Algebra Problem: Solving for Euler between two ordered bases

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  9. H

    Find theta given known cos and sin....

    Homework Statement Homework Equations cos 2theta = costheta^2 - sintheta^2 The Attempt at a Solution cos2theta = 1 2theta = 0, 2phi but i get wrong answer.. how is it?
  10. H

    Multiple in logarithm question -- find the variable?

    Homework Statement Homework Equations $$ \log_{x} a \ means \ 10^x = a $$ $$ \log_{x} {a^n} = n \log_{x}{a} $$ The Attempt at a Solution $$ \log_{10} {ax} \log_{10}{bx} + 1 = 0 $$ $$ \ means \log_{10} {ax} = 1 \log_{10}{bx} = -1 \ or \ vice \ versa $$ $$ \ for \log_{10} {ax} = 1 \ so \ ax...
  11. H

    The 2 absolute equation equality? find the max and min of x?

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  12. H

    5 degree equation contains imaginary value?

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  13. SetepenSeth

    Linear Algebra - Kernel and range of T

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  14. N

    Analysis Good books on linear algebra and real/complex analysis?

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  15. Const@ntine

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  16. SetepenSeth

    Linear Algebra - Standard Matrix of T

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  17. SetepenSeth

    Linear Algebra - Linearity of a transformation

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  18. D

    Complete the table for the finite field

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  19. SinaloanGods

    Need Algebra Studying Resource Help (Thanks)

    About to start reviewing for a math test but it has been ages since I was in school. Hoping some of you math savants could help me out. Will hope to understand and be able to complete these two exams. Starting with the first one below. (Do you guys know of a better exam to test and know...
  20. SetepenSeth

    Linear Algebra - Linear (in)dependence of a set

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  21. mr.tea

    Algebra Question Regarding Purchasing an Algebra Book

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  22. Jehannum

    B Algebra Help Needed: Understanding Algebraic Manipulations and Techniques

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  23. DaTario

    I Question about the Fundamental Theorem of Algebra

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  24. S

    I Lie Algebra of Lorentz group

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  25. awholenumber

    Looking for some order to learn algebra

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  26. arnbobo

    Schools Will a B in Linear Algebra hurt my grad school chances?

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  27. H Psi equal E Psi

    I Affine transformation and coordinates of maps

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  28. binbagsss

    Strings - Visaro operators - basically commutator algebra

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  29. M

    An equation for an algebra word problem

    Homework Statement Suppose that b is 20% more than a, c is 25% more than b, and d is k% less than c. Find k such that a=d Homework Equations a=d; b=1.2a; c=1.25b=1.5aThe Attempt at a Solution 1. a=##\frac{c}{15 }##=d=##\frac{100c-k}{100}## 2. By multiplication of extremes and means we get...
  30. Mr Davis 97

    I Why are polynomials defined the way they are in algebra?

    I've always been curious about why we define polynomials the way we do. On the surface, it seems that they are expressions that naturally arise from combining the standard arithmetic operations on indeterminates. However, there are some points that I am generally confused about. Why are...
  31. jlmccart03

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  32. Bunny-chan

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  33. Phylosopher

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  34. Milsomonk

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  35. V

    B Solve for n How can we use logarithms to solve for the variable in this equation?

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  36. binbagsss

    Is the Expression Valid in Demonstrating a Poincare Algebra Commutator?

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  37. Bobs

    I Solve 2x+3y=0: Find x & y Points for Line

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  38. B

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  39. Ian Baughman

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  40. F

    I Integral involving square and log

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  41. R

    Boolean Algebra Simplification

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  42. S

    A Extracting Tensor Algebra Term with SU(N) Generators and Numbers

    Consider the expression $$\left(T^{a}\partial_{\mu}\varphi^{a} + A_{\mu}^{a}\varphi^{b}[T^{a},T^{b}] + A_{\mu}^{a}\phi^{b}[T^{a},T^{b}]\right)^{2},$$ where ##T^{a}## are generators of the ##\textbf{su}(N)## Lie algebra, and ##\varphi^{a}##, ##\phi^{a}## and ##A_{\mu}^{a}## are numbers. How...
  43. O

    B What were the contributions of the hidden figures to the early space program?

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  44. A

    Linear Algebra - what is Re and Im for complex numbers?

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  45. Z

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  46. UsableThought

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  47. Alex Salazar

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  48. N

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  49. CynicusRex

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  50. B

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