The values of x for which the given matrix le | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) Let $A = \left[\begin{array}{ccc}-x & x & 2 \ 2 & x & -x \ x & -2 & -2\end{array}ight]$.$A$ matrix $A$ is non-singular if and only if its dete

Vedclass · Accepted Answer

for all $x$ other than $2$ and $-2$

Vedclass · Answer

(B) Let $A = \left[\begin{array}{ccc}-x & x & 2 \ 2 & x & -x \ x & -2 & -2\end{array}ight]$.$A$ matrix $A$ is non-singular if and only if its determinant $|A| 
eq 0$.Calculating the determinant $|A|$:$|A| = -x \begin{vmatrix} x & -x \ -2 & -2 \end{vmatrix} - x \begin{vmatrix} 2 & -x \ x & -2 \end{vmatrix} + 2 \begin{vmatrix} 2 & x \ x & -2 \end{vmatrix}$$|A| = -x(-2x - 2x) - x(-4 + x^2) + 2(-4 - x^2)$$|A| = -x(-4x) + 4x - x^3 - 8 - 2x^2$$|A| = 4x^2 + 4x - x^3 - 8 - 2x^2$$|A| = -x^3 + 2x^2 + 4x - 8$For the matrix to be non-singular,$|A| 
eq 0$:$-x^3 + 2x^2 + 4x - 8 
eq 0$$-(x^3 - 2x^2 - 4x + 8) 
eq 0$$-(x^2(x - 2) - 4(x - 2)) 
eq 0$$-(x^2 - 4)(x - 2) 
eq 0$$-(x - 2)(x + 2)(x - 2) 
eq 0$$-(x - 2)^2(x + 2) 
eq 0$Therefore,$x 
eq 2$ and $x 
eq -2$.Thus,the matrix is non-singular for all $x$ other than $2$ and $-2$.

The values of $x$ for which the given matrix $\left[\begin{array}{ccc}-x & x & 2 \\ 2 & x & -x \\ x & -2 & -2\end{array}\right]$ will be non-singular are

Similar Questions

The constant term of the polynomial $\left|\begin{array}{ccc}x+3 & x & x+2 \\ x & x+1 & x-1 \\ x+2 & 2x & 3x+1\end{array}\right|$ is

The matrix $\begin{bmatrix} 1 & a & 2 \\ 1 & 2 & 5 \\ 2 & 1 & 1 \end{bmatrix}$ is not invertible if $a$ has the value:

The roots of the equation $\left| \begin{array}{ccc} x-1 & 1 & 1 \\ 1 & x-1 & 1 \\ 1 & 1 & x-1 \end{array} \right| = 0$ are

The value of $x$ such that the matrix $\begin{bmatrix} x & 2 & 3 \\ 4 & 5 & 6 \\ 2 & 3 & 5 \end{bmatrix}$ is not invertible is

If $\Delta=\left|\begin{array}{lll}1 & a & a^2 \\ 1 & b & b^2 \\ 1 & c & c^2\end{array}\right|=K(a-b)(b-c)(c-a)$, then $K=$

Vedclass Test Series

Exam Paper Generator

Online Exam Module