Echelon form is used to simplify a complex matrix into a simpler form by using row operations. A matrix is in echelon form if it has increasing numbers of zeros as the row number increases, and any rows of all zeros are at the bottom. For example, a 4x4 matrix is converted into echelon form by performing row operations to make the principal diagonal elements non-zero and elements below them zero, resulting in a matrix with rank 2 as indicated by the number of non-zero rows.
3. Echelon’s Form:
Echelon Form of a matrix is used to solve a complex matrix to a simple matrix.
A matrix is in an Echelon Form if it satisfies some below given conditions:
The number of zero’s are increased by the row number before the non- zero elements.
If zero rows are exist that row is at the end of the matrix.
Note: A given matrix can be converted into echelon’s form by using row operations only.
4. For Example:
Q)
𝟏 𝟐 𝟑 −𝟏
−𝟐 −𝟏 −𝟑 −𝟏
𝟏 𝟎 𝟏 𝟏
𝟎 𝟏 𝟏 𝟏
Ans:
𝟏 𝟐 𝟑 −𝟏
−𝟐 −𝟏 −𝟑 −𝟏
𝟏 𝟎 𝟏 𝟏
𝟎 𝟏 𝟏 𝟏
Principal Diagonal Elements
Note: You have to make all zero’s below the principal
diagonal elements by using row operation.
R2 = R2+2R1, R3 = R3-R1
5.
𝟏 𝟐 𝟑 −𝟏
𝟎 𝟑 𝟑 −𝟑
𝟎 −𝟐 −𝟐 𝟐
𝟎 𝟏 𝟏 −𝟏
R3 = 3R3+2R2, R4 = 3R4-R2
𝟏 𝟐 𝟑 −𝟏
𝟎 𝟑 𝟑 −𝟑
𝟎 𝟎 𝟎 𝟎
𝟎 𝟎 𝟎 𝟎
∴ The above matrix is in the form of Echelon’s Form.
Now, We have to find the rank of the matrix.
To find the rank of the matrix, we have to consider
the non zero rows as the rank of matrix.
Now, the rank of above matrix is 2.
∴ (𝐴) = 2