Let A = 5 5 0 5 00 5 a a a a . If 2 A = 25 , then a equals

Question:

Let $A=\left|\begin{array}{ccc}5 & 5 \alpha & \alpha \\ 0 & \alpha & 5 \alpha \\ 0 & 0 & 5\end{array}\right|$. If $\left|A^{2}\right|=25$, then $|\alpha|$ equals

  1. $1 / 5$

     

  2. 5

  3. $5^{2}$

  4. 1


Correct Option: 1

JEE Main Previous Year 1 Question of JEE Main from Mathematics Matrices and Determinants chapter.
JEE Main Previous Year 2007

Solution:

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