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. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 43: Computation of the rank of a matrix

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 43: Computation of the rank of a matrix

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  2. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 44: Elementary matrices

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 44: Elementary matrices

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  3. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 45: Elementary operations on matrices

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 45: Elementary operations on matrices

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  4. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 46: LR decomposition

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 46: LR decomposition

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  5. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 47: Elementary Divisor Theorem

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 47: Elementary Divisor Theorem

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  6. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 48: Permutation groups

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 48: Permutation groups

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  7. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 49: Canonical cycle decomposition of permutations

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 49: Canonical cycle decomposition of permutations

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  8. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 50: Signature of a permutation

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 50: Signature of a permutation

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  9. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 51: Introduction to multilinear maps

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 51: Introduction to multilinear maps

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  10. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 52: Multilinear maps continued

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 52: Multilinear maps continued

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  11. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 53: Introduction to determinants

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 53: Introduction to determinants

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  12. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 54: Determinants continued

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 54: Determinants continued

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  13. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 55: Computational rules for determinants

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 55: Computational rules for determinants

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  14. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 56: Properties of determinants and adjoint of a matrix

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 56: Properties of determinants and adjoint of a matrix

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  15. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 57: Adjoint determinant theorem

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 57: Adjoint determinant theorem

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  16. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 58: The determinant of a linear operator

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 58: The determinant of a linear operator

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  17. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 59: Determinants and Volumes

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 59: Determinants and Volumes

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
  18. Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 60: Determinants and Volumes continued

    Linear Algebra by Prof. Dilip Patil (NPTEL):- Lecture 60: Determinants and Volumes continued

    COPYRIGHT strictly reserved to Prof. Dilip P. Patil and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/111108098/ Syllabus: http://www.nptel.ac.in/syllabus/syllabus.php?subjectId=111108098
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