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For any 2xx2 matrix, if A\ (a d j\ A)=[[...

For any `2xx2` matrix, if `A\ (a d j\ A)=[[10 ,0 ],[0 ,10]]` , then `|A|` is equal to (a) 20 (b) 100 (c) 10 (d) 0

A

20

B

100

C

10

D

0

Text Solution

Verified by Experts

The correct Answer is:
C
We know that for any square matrix A.
`A(adjA) =absAI`
`:. A (adjA)={:[(10,0),(0,10)]:}=10I_2rArrabsAI_2=10I_2rArrabsA=10`
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OBJECTIVE RD SHARMA ENGLISH-MATRICES-Section I - Solved Mcqs
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