The value of the determinant left| begin{arra | vedclass

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

Question

(B) Let $\Delta = \left| \begin{array}{ccc} 31 & 37 & 92 \ 31 & 58 & 71 \ 31 & 105 & 24 \end{array} ight|$.Applying the row operations $R_2 	o R_

Vedclass · Accepted Answer

$0$

Vedclass · Answer

(B) Let $\Delta = \left| \begin{array}{ccc} 31 & 37 & 92 \ 31 & 58 & 71 \ 31 & 105 & 24 \end{array} ight|$.Applying the row operations $R_2 	o R_2 - R_1$ and $R_3 	o R_3 - R_1$:$\Delta = \left| \begin{array}{ccc} 31 & 37 & 92 \ 31-31 & 58-37 & 71-92 \ 31-31 & 105-37 & 24-92 \end{array} ight|$$\Delta = \left| \begin{array}{ccc} 31 & 37 & 92 \ 0 & 21 & -21 \ 0 & 68 & -68 \end{array} ight|$Since the second and third rows are proportional (or by factoring out $21$ from $R_2$ and $68$ from $R_3$,we get identical columns),the determinant is $0$.Specifically,$R_3 = \frac{68}{21} R_2$,so the rows are linearly dependent.Therefore,$\Delta = 0$.

The value of the determinant $\left| \begin{array}{ccc} 31 & 37 & 92 \\ 31 & 58 & 71 \\ 31 & 105 & 24 \end{array} \right|$ is

Similar Questions

If $A \neq O$ and $B \neq O$ are $n \times n$ matrices such that $AB = O$,then

$\left| {\begin{array}{*{20}{c}}1&a&{{a^2}}\\1&b&{{b^2}}\\1&c&{{c^2}}\end{array}} \right| = $

If $A = \begin{bmatrix} \alpha & 2 \\ 2 & \alpha \end{bmatrix}$ and $|A^3| = 125$,then $\alpha = $ . . . . . .

If $A = \begin{bmatrix} 1 & 1 & -2 \\ 2 & 1 & -3 \\ 5 & 4 & -9 \end{bmatrix}$,find $|A|$.

Let $A = \begin{bmatrix} 2 & 0 & 3 \\ 4 & 7 & 11 \\ 5 & 4 & 8 \end{bmatrix}$. Then

Vedclass Test Series

Exam Paper Generator

Online Exam Module