Matrix Multiplication In Excel How To Help Her

Matrix Multiplication In Excel How To Help Her

It had been many years since I have had algebra and parts of it made sense but I couldnt quite grasp how to help her.

In this section we consider the topic of Vectors, Matrices and Arrays and their application in solving Linear Equations and other linear algebra problems.

Excels Solver feature will be used in a later chapter to solve more complicated linear and nonlinear systems of equations.

Matrices consisting of a single row or a single column are called vectors.

Even though the functions are named with matrix there is no help in Excel under matrix only array.

Such a formula uses matrix functions and returns a result that can be a matrix, a vector, or a scalar, depending on the computations involved.

Whatever the result may be, an area on the spreadsheet of precisely the correct size must be selected before the formula is typed in (otherwise you will either lose some of the answer or get added and possibly confusing information).

This indicates that a matrix (array) result really is desired.

It also designates the entire selected range as the desired location for the answer.

To modify or delete the formula, select the entire region beforehand.

This feature, coupled with the ability to see matrices, complete with identification of the rows and columns (i.e.

This is done by typing A in the name field of the function picker.

This will introduce characters around the formula AB which indicate an array operation.

The number of columns in the first matrix must equal the number of rows in the second matrix.

That is, you can multiple A(2,5)xB(5,3) because the inner numbers are the same.

The size of the result is governed by the outer numbers, in this case (2,3).

Hence, a row vectors transpose is a column vector and the transpose of a 2x3 matrix is a 3x2 matrix.

The matrix must be square (same number of rows and columns) 2.

Any row or column is a linear combination of other rows or columns.

Since the calculation of a determinant involves a significant number of calculations, it is subject to round-off error.

When the determinant is essentially zero (that is, 1x10-14 or less) it can be considered zero.

Ax b. 2. Invert the coefficient matrix A -1 3.

Multiply both sides of the equation by the inverted coefficient matrix.

Matrix Multiplication In Excel For Mac