Explanation:
Matrix
(mathematics)
Specific
elements of a matrix are often denoted by a variable with two subscripts. For
instance,a_{2,1} represents the element at the second row and first
column of a matrix A.
In mathematics, a matrix (plural matrices, or
less commonly matrixes) is a
rectangular array of numbers, symbols, or expressions. The individual items in
a matrix are called its elements or entries. An example
of a matrix with six elements is
Matrix multiplication
Schematic
depiction of the matrix product AB of two
matrices A and B.
Multiplication of two matrices is defined
only if the number of columns of the left matrix is the same as the number of
rows of the right matrix. If A is an m-by-n matrix and B is an n-by-p matrix, then their matrix product AB is the m-by-p matrix whose entries are
given by dot product of the corresponding row of A and the corresponding column
of B:
where 1 ≤ i ≤ m and 1 ≤ j ≤ p.
(Our solved example in mathguru.com uses this
concept)
For example,
the underlined entry 1 in the product is calculated as (1 × 1) + (0 × 1) + (2 × 0) = 1:
http://en.wikipedia.org/wiki/Matrix_(mathematics)
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above explanation is copied from Wikipedia, the free encyclopedia and is
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License.