Solving linear Equations

Matrix row-reduction

  • To solve linear equation using traditional method, we use elimination. Similarly we use row reduction when using matrices to solve linear equations

  • Row echelon form

  • Matrix row-reduction

  • Row echelon form for singular matrix

Row operations

  • Row operations preserve the singularity of the matrix i.e singular matrix will be singular and non-singular matrix will be non-singular after row operations
  • row operations are -
    • switching rows
    • Multiplying a row by a non-zero scalar
    • Adding a row to another row

The Rank of a Matrix

  • It is a measure of the information that matrix or its corresponding system of linear equations is carrying

  • Matrices with reduced rank will take less space for storage

  • Matrices with reduced rank to compress the images

  • Rank fo a matrix

  • There is a relationship between Rank of a Matrix and its solution space.

  • Rank = number of rows in a matrix - Dimension of solution space

  • A matrix is non-singular if and only if it has full rank. The number of rows is equal to the rank of the matrix

  • Rank and Solution space of a Matrix

  • Rank of matrices

Row Echelon Form of a Matrix

  • Calculations to get Row Echelon Form

  • Rank of a matrix is the number of 1’s in the diagonal of row echelon form (for the below figure)

  • Relation between Row Echelon form, Singularity and Rank

  • Row Echelon for Bigger Matrices

Reduced Row Echelon Form

  • Reduced row echelon form is equivalent to the solved system

  • Generalized form of Reduced row echelon

  • Calculating Reduced row echelon

Reference