Q. 43

# If A is an invertible matrix and A^{-1} = then A=?

A.

_{B.}

_{C.}

_{D.None of these}

Answer :

y property of inverse

(A^{-1})^{-1} = A

(A^{-1})^{-1} =^{-1}

A =^{-1} ------------ 1

^{-1} = 3 x 6 – 4 x 5

-2

C_{11} = 6 C_{12} = -5

C_{21}= -4 C_{22} = 3

Cofactor matrix A =

Adj A =

^{-1} =

=

Putting in 1

A =

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