A) \[2A+B=0\]
B) \[2A-B=0\]
C) \[A+2B=0\]
D) \[A-2B=0\]
Correct Answer: B
Solution :
| \[B=2.2\left| \begin{matrix} f & d & e \\ n & \ell & m \\ c & a & b \\ \end{matrix} \right|\][Taking 2 common from \[{{R}_{2}}\]and \[{{C}_{2}}\]] \[=2\,\,\left| \begin{matrix} 2f & d & e \\ 2n & \ell & m \\ 2c & a & b \\ \end{matrix} \right|=2\,\,\left| \begin{matrix} 2c & a & b \\ 2f & d & e \\ 2n & \ell & m \\ \end{matrix} \right|\] |
| \[[{{R}_{3}}\leftrightarrow {{R}_{2}},\,\,then\,\,{{R}_{2}}\leftrightarrow {{R}_{1}}]\] |
| \[=2\,\,\left| \begin{matrix} a & b & 2c \\ d & e & 2f \\ \ell & m & 2n \\ \end{matrix} \right|=2A\] \[[{{C}_{1}}\leftrightarrow {{C}_{2}}\,\,and\,\,then\,\,{{C}_{2}}\leftrightarrow {{C}_{3}}]\] |
You need to login to perform this action.
You will be redirected in
3 sec
