If (A = \left| \begin{matrix} 1 & 2 & 4 \\ 3 & 1 & 0 \\ 2... | MATH - EXPANSION OF DETERMINANTS, SOLUTION OF EQUATION | SolveeIt | Solveeit

Today, August 18

Question

If $A = \left| \begin{matrix}

1 & 2 & 4 \ 3 & 1 & 0 \
2 & 4 & 2 \end{matrix} \right| $and$ B = \left| \begin{matrix}
2 & 4 & 2 \ 6 & 2 & 0 \
2 & 4 & 8 \end{matrix} \right|$, then B is given by.

A

$B = 4A$

B

$B = - 4A$

C

$B = - A$

D

$B = 6A$

Answer

$B = - 4A$

Explanation

Solution

B is obtained from A by the operations

$R_{1} \leftrightarrow R_{3},R_{3} \rightarrow 2R_{3}$ and $(\sin^{2}60^{o} + \sin^{2}60^{o} + \sin^{2}60^{o})$ .

Hence, $B = ( - 1)4A = - 4A$ .