Given I_{2}. Find determinant I_{2}. also find determinant 3I_{2}.

_{2}is an identity matrix of second order

So I

_{2}= $\left[\begin{array}{cc}1& 0\\ 0& 1\end{array}\right]$

And det(I

_{2}) = 1*1 - (0*0) = 1

And 3I

_{2}means all the element are multiplied by 3.

Hence 3I

_{2}

_{ }= $\left[\begin{array}{cc}3& 0\\ 0& 3\end{array}\right]$

Hence det(3I

_{2}

_{ }) = 3*3 - 0*0 = 9 (ans)

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