Q. 1. Determine the rank of the matrix: A=⎣⎡101110111⎦⎤
Write Matrix A: Write down the matrix A.A=[111011101]We need to determine the rank of this matrix, which is the dimension of the vector space spanned by its rows (or columns).
Check Row Dependence: Check if any rows are linearly dependent.For matrix A, no rows are multiples of each other, so we cannot immediately identify any linearly dependent rows.
Perform Row Reduction: Perform row reduction to echelon form to identify the rank.We will use elementary row operations to convert the matrix into row echelon form.Starting with matrix A:A = \left[\begin{array}{ccc}\(\newline1 & 1 & 1 (\newline\)0 & 1 & 1 (\newline\)1 & 0 & 1\end{array}\right]\)Subtract the first row from the third row to make the first element of the third row zero:R3=R3−R1A = \left[\begin{array}{ccc}\(\newline1 & 1 & 1 (\newline\)0 & 1 & 1 (\newline\)0 & -1 & 0\end{array}\right]\)Now, add the third row to the second row to make the second element of the second row zero:R2=R2+R3A = \left[\begin{array}{ccc}\(\newline1 & 1 & 1 (\newline\)0 & 0 & 1 (\newline\)0 & -1 & 0\end{array}\right]\)Finally, add the third row to the first row to make the second element of the first row zero:R1=R1+R3A = \left[\begin{array}{ccc}\(\newline1 & 0 & 1 (\newline\)0 & 0 & 1 (\newline\)0 & -1 & 0\end{array}\right]\)
Identify Non-Zero Rows: Identify the number of non-zero rows in the row echelon form.In the row echelon form of matrix A, we have:A = \left[\begin{array}{ccc}\(\newline1 & 0 & 1 (\newline\)0 & 0 & 1 (\newline\)0 & -1 & 0\end{array}\right]\)All 3 rows are non-zero, which means they are linearly independent.
Determine Rank: Determine the rank of the matrix.Since all three rows are linearly independent, the rank of matrix A is equal to the number of non-zero rows in its row echelon form.