Math 2.0

Linear and multilinear algebra; matrix theory Definition

Matrix addition

Builds on Matrix

Definition

Let RR be a ring and let A=(aij)A = (a_{ij}) and B=(bij)B = (b_{ij}) be m×nm \times n matrices over RR. The sum A+BA + B is the m×nm \times n matrix with entries (A+B)ij=aij+bij(A + B)_{ij} = a_{ij} + b_{ij} for 1≤i≤m1 \le i \le m and 1≤j≤n1 \le j \le n.

Remarks

The sum is defined only for two matrices of the same size. Matrix addition is associative and commutative, the zero matrix is its identity element, and −A=(−aij)-A = (-a_{ij}) is the additive inverse of AA. Thus Mm×n(R)M_{m \times n}(R) is an abelian group under addition. For example, (1234)+(0110)=(1344)\begin{pmatrix} 1 & 2 \\ 3 & 4 \end{pmatrix} + \begin{pmatrix} 0 & 1 \\ 1 & 0 \end{pmatrix} = \begin{pmatrix} 1 & 3 \\ 4 & 4 \end{pmatrix}.

Reading path

To understand this page from the ground up, read these 2 pages in order. The foundations come first.

Show the path as a graph
Each page uses the pages above it. The colour of the bar on a box shows how strong the evidence is, and the box also gives it as text. The list has the same pages.
  • no evidence level
  1. Matrix definition
  2. Matrix addition definition

Where this leads

2 pages build on this one.

Further reading

  1. Web https://en.wikipedia.org/wiki/Matrix_addition, lead section
About this page
Tag0BVXADM10P
URIm2://0BVXADM10P
Kinddefinition
WritingW1 stated
MSC15A99
DefinesMatrix addition
UsesMatrix

Markdown · JSON · Edit on GitHub

What this page needs for W2

  • edge instance_of in: one example (0 of 1)
  • edge not_instance_of in: one non-example that fails one clause (0 of 1)

The writing levels say how complete the text of a page is. They do not measure its truth.

What links here

Used by