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Let A= [[5,5alpha,alpha],[0,alpha,5alph...

Let ` A= [[5,5alpha,alpha],[0,alpha,5alpha],[0,0,5]]` .` If A^2 = 25,` then `alpha` equals to:

A

`5^(2)`

B

1

C

`1//5`

D

5

Text Solution

Verified by Experts

The correct Answer is:
C
`A = [[5, 5alpha ,alpha ],[0,alpha,alpha5],[0,0,5]]rArr abs(AcdotA)= abs(A) abs(A)= (25alpha)^(2) = 25`
`rArr alpha^(2) = 1/25`
`rArr alpha = pm1/5`
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