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CUET
-- Mathematics - Section A
Matrices
If A is a non singular square matrix of order 3 such that $A^3=4A^2$ then value of |A| is :
16
64
4
8
$A^3=4A^2$
so $A^3A^{-1}=4A^2A^{-1}⇒A^2=4A$ post multiplying by $A^{-1}$
$A^2A^{-1}=4AA^{-1}⇒A=4I$
so $|A|=4^3|I|$ as order is 3
so $|A|=64$