# Given I2. Find determinant I2. also find determinant 3I2.

As I2 is an identity matrix of second order
So I2 = $\left[\begin{array}{cc}1& 0\\ 0& 1\end{array}\right]$
And det(I2 ) = 1*1 - (0*0) = 1

And 3I2 means all the element are multiplied by 3.
Hence  3I2  = $\left[\begin{array}{cc}3& 0\\ 0& 3\end{array}\right]$
Hence det(3I2 )  = 3*3 - 0*0 = 9 (ans)

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