What is the reduced row echelon form of a matrix
To convert a matrix to the reduced row-echelon form, we ensure the following conditions:
Each leading entry (first non-zero element) for a non-zero row should be equal to 1 and should have all zero elements to its left, bottom, and above.
All
should be placed at the end of the matrix.zero rows Rows in which all elements are 0.
For a matrix A, we represent this as:
Here the leading entry for the 1st row and 2nd row is
Basic and non-basic column
In a matrix of reduced row echelon form, basic columns are matrix columns that contain a leading entry, while non-basic columns are columns that don't have a leading entry.
Following is the example of a matrix
Here the 1st column is a basic column with leading entry
Converting a matrix to reduced row-echelon form
To convert a simple matrix to reduced row echelon form, we use the Gaussian elimination method approach. This approach mainly involves the following steps:
Interchanging any two rows
Adding any two rows
Multiplying a row by a
with a non-zero value.scalar A numerical value.
Note: We can perform any two of the above steps together at the same time.
Example
Consider an example of converting a matrix to a reduced row-echelon form. Suppose we have a matrix
The leading entry of the 1st row is 1. Since it is the 1st row, there are no elements above it, so we only convert all the elements below it to 0.
We multiply the 1st row by -3 and add it to the 2nd row:
We multiply the 1st row by -1 and add it to the 3rd row:
The leading entry of the 2nd row is -1, so we multiply the 2nd row with -1.
The leading entry of the 2nd row is now 1, and all the elements below it are already 0. We convert the element above it to 0 now.
We multiply the 2nd row by -2 and add it to the 1st row:
Our final result is:
Conclusion
The reduced row echelon form is a powerful tool in linear algebra. It helps us simplify our matrices so we can apply operations on them. Moreover, it gives a clear structure to determine relationships within matrices, contributing to efficient problem-solving across various fields.
Free Resources