Multiplication of two matrices is possible if the number of columns in the first matrix equals the number of rows in the second matrix.
Let A be the first matrix and B be the second matrix.
\The dimensions of the first matrix A are , so the number of the columns in the first matrix is 2.
The dimensions of the second matrix B are , so the number of the rows in the second matrix B is 2.
The number of columns in the first matrix equals the number of rows in the second matrix. So, matrix product is possible and its dimensions are .
Let P be the matrix product.
\The matrix P is
\The element
of the matrix (
) is the sum of the products of the corresponding elements in the i th row of the first matrix (
) and column j th column of the second matrix (
).
where
is the row index and
.
Find the element
.
The element is the sum of the products of the corresponding elements of row 1 of the matrix A and column 1 of the second matrix.
.
Next find the element
.
The element is the sum of the products of the corresponding elements of row 1 of the matrix A and column 2 of the second matrix.
.
Next find the element
.
The element is the sum of the products of the corresponding elements of row 1 of the matrix A and column 3 of the second matrix.
.
Next find the element
.
The element is the sum of the products of the corresponding elements of row 2 of the matrix A and column 1 of the second matrix.
.
Next find the element
.
The element is the sum of the products of the corresponding elements of row 2 of the matrix A and column 2 of the second matrix.
.
Next find the element
.
The element is the sum of the products of the corresponding elements of row 2 of the matrix A and column 3 of the second matrix.
.
Next find the element
.
The element is the sum of the products of the corresponding elements of row 3 of the matrix A and column 1 of the second matrix.
.
Next find the element .
The element is the sum of the products of the corresponding elements of row 3 of the matrix A and column 2 of the second matrix.
.
Next find the element .
The element is the sum of the products of the corresponding elements of row 3 of the matrix A and column 3 of the second matrix.
.
Simplify the product matrix.
\The product matrix is