What is Linear algebra: Definition and 999 Discussions

Linear algebra is the branch of mathematics concerning linear equations such as:





a

1



x

1


+

+

a

n



x

n


=
b
,


{\displaystyle a_{1}x_{1}+\cdots +a_{n}x_{n}=b,}
linear maps such as:




(

x

1


,

,

x

n


)


a

1



x

1


+

+

a

n



x

n


,


{\displaystyle (x_{1},\ldots ,x_{n})\mapsto a_{1}x_{1}+\cdots +a_{n}x_{n},}
and their representations in vector spaces and through matrices.Linear algebra is central to almost all areas of mathematics. For instance, linear algebra is fundamental in modern presentations of geometry, including for defining basic objects such as lines, planes and rotations. Also, functional analysis, a branch of mathematical analysis, may be viewed as the application of linear algebra to spaces of functions.
Linear algebra is also used in most sciences and fields of engineering, because it allows modeling many natural phenomena, and computing efficiently with such models. For nonlinear systems, which cannot be modeled with linear algebra, it is often used for dealing with first-order approximations, using the fact that the differential of a multivariate function at a point is the linear map that best approximates the function near that point.

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  1. Dany

    Master Linear Algebra: A Beginner's Guide to Vectors for Physics Students

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  2. BiGyElLoWhAt

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  3. BiGyElLoWhAt

    Question about notation in Linear Algebra

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  4. T

    Calculus 3 -- should I take linear algebra before or can I take it after?

    I will start calculus 2 in the fall. I am comfortable with the integration techniques. I did not quite get Taylor series an d the like during self study. I can learn this from the professor swing that I have somewhat completed the cal 2 portion and the semester is 2 months away. now my...
  5. J

    Partial Differential Equations vs Linear Algebra

    This semester I'm a bit stuck with classes to progress my Electrical Engineering major (having going into it so late), so the only class I can take to progress is a physics course about electricity and the likes. I need at least a three unit class in order to get at least half time so I won't...
  6. M

    [Linear Algebra] Pouring Problem

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  7. kq6up

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  8. M

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  9. S

    Possibly silly linear algebra question

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  10. L

    Linear Algebra Transition Matrix Proof

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  11. caffeinemachine

    MHB Looking for an Example of an Amusing Theorem in Linear Algebra.

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  12. M

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  13. N

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  14. W

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  15. D

    Is S a Subspace of P_3 and Does q(x) Belong in S?

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  16. S

    Discrete Math or Linear Algebra.

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  17. N

    Proving |det(1+A)|^2 >=1 by Diagonalizing iA: Linear Algebra Question

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  18. N

    Linear ALgebra: Showing negative definteness

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  19. M

    How Do You Construct a Matrix with a Specific Null Space?

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  20. P

    MHB New to Linear Algebra - LU Decomposition

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  21. C

    How Do You Solve a Plane Equation in R^4 and Find Its Normalized Normal?

    Homework Statement Find equation of plan H in R^4 that contains the point P= (2,-1,10,6) and is parallel to plain H2: 4a +4b + 5c-6d = 3 then answer the following questions: A. find normalized normal of plane H which has an angle theta with the normal n= (4,4,5,-6) of H2 such that...
  22. N

    Linear Algebra: linear transformation

    Homework Statement We have seen that the linear transformation ##T(x_1,x_2)=(x_1,0)## on ##\mathcal{R}^2## has the matrix ##A = \left( \begin{smallmatrix} 1&0\\ 0&0 \end{smallmatrix} \right)## with respect to the standard basis. This operator satisfies ##T^2=T##. Prove that if...
  23. D

    Linear Algebra. Are my methods and solutions correct?

    Consider the following three vectors in R3: u1=(3,6,2) , u2=(-1,0,1) , u3=(3,λ,7) a) Find all values of λ E R, such that {u1, u2, u3} spans R3, i.e.R3 = span {u1, u2, u3} b) Find the value of λ E R, such that {u1, u2, u3} spans a plane in R3. c) Find all values of k E R, such that the...
  24. T

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  25. Chacabucogod

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  26. T

    Linear Algebra Proof: Dim(X)=n, Show nk Dim Vector Space

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  27. N

    Linear Algebra Eigenspace Question

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  28. jbrussell93

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  29. C

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  30. C

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  31. M

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  32. C

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  33. S

    MHB What is vector in linear algebra

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  34. W

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  35. G

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  36. C

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  37. B

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  38. T

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  39. U

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  40. ME_student

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  41. N

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  42. F

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  43. M

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  44. C

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  45. Y

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  46. B

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  47. T

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  48. E

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  49. U

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  50. I

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