Q. $\left| \begin{matrix} 1 & 5 & \pi \\ \log_{e}e & 5 & \sqrt{5} \\ \log_{10}10 & 5 & e \end{matrix} \right|$ is equal to

A) $\sqrt{\pi}$
B) $e$
C) 1
D) 0
Explanation

(d)
Let $\mathrm{\Delta} = \left| \begin{matrix}
1 & 5 & \pi \\
\log_{e}e & 5 & \sqrt{5} \\
\log_{10}10 & 5 & e
\end{matrix} \right|$
$\Rightarrow \ \mathrm{\Delta} = \left| \begin{matrix}
1 & 5 & \pi \\
1 & 5 & \sqrt{5} \\
1 & 5 & e
\end{matrix} \right| = 5\left| \begin{matrix}
1 & 1 & \pi \\
1 & 1 & \sqrt{5} \\
1 & 1 & e
\end{matrix} \right|$ $(\because\log_{a}{a = 1)}$
$= 0\$ $(\because$ two columns are identical)

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.

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