The number of elements in the set Extra \left or missing \right\left\{A=\begin{pmatrix}a&b\\0&d\end{pmatrix}:a,b,d\in\{-1,0,l\} and Missing \left or extra \right(I-A)^3=I-A^3\right\}, where I is 2 × 2 identity matrix , is :
Question ID VK-025460