If A is an invertible matrix of order 2, then A-1 is equal to?
A
1A
1
0
Explanation of correct answer:
Since,
AA-1=I
Now, taking determinant on both sides
⇒AA-1=I [AB=AB]
⇒AA-1=1 [ I=1]
⇒ A-1=1A [A≠0]
Thus, A-1 is equal to 1A.
Hence, Option(B) is correct.
If A is an invertible matrix of order 2, then det (A−1) is equal to
A. det (A) B. C. 1 D. 0