For which value of x, will the matrix \(\left[ {\begin{array}{*{20}{c}} 8&x&0\\ 4&0&2\\ {12}&6&0 \end{array}} \right]\) become singular.
4
The question asks us to find the specific value of x that will make the given matrix singular. A matrix is defined as singular if its determinant is equal to zero.
The matrix provided is:
| $$ 8 $$ | $$ x $$ | $$ 0 $$ |
| $$ 4 $$ | $$ 0 $$ | $$ 2 $$ |
| $$ 12 $$ | $$ 6 $$ | $$ 0 $$ |
Let's denote this matrix as A.
To find the value of x that makes the matrix singular, we first need to calculate its determinant, denoted as $ \det(A) $. We can use the cofactor expansion method. Let's expand along the first row:
Now, we calculate the determinants of the 2x2 matrices:
Substitute these values back into the determinant formula:
$$ \det(A) = 8(-12) - x(-24) + 0(24) $$ $$ \det(A) = -96 + 24x + 0 $$ $$ \det(A) = -96 + 24x $$For the matrix to be singular, its determinant must be zero. So, we set $ \det(A) = 0 $:
$$ -96 + 24x = 0 $$Now, we solve this linear equation for x:
Therefore, the value of x that makes the matrix singular is 4.
If \({\rm{A}} = \left[ {\begin{array}{*{20}{c}} 1&1&{ - 1}\\ 2&{ - 3}&4\\ 3&{ - 2}&3 \end{array}} \right]{\rm{\;and\;\;B}} = \left[ {\begin{array}{*{20}{c}} { - 1}&{ - 2}&{ - 1}\\ 6&{12}&6\\ 5&{10}&5 \end{array}} \right]\) then which of the following is/are correct?
1. A and B commute.
2. AB is a null matrix.
Select the correct answer using the code given below:Which one of the following matrices is an elementary matrix?
The matrix is \(\left[ {\begin{array}{c} 0&{ - 4 + i}\\ {4 + i}&0 \end{array}} \right]\)
How many distinct matrices exist with all four entries taken from (1, 2)?
If A and B are square matrices of order 2 such that det(AB) = det(BA), then which one of the following is correct?