Question

Let \( A=\left(\begin{array}{cc}2 & -1 \\ 0 & 2\end{array}\right) \). If \( B=I-{ }^{5} C_{1}(\operatorname{adj} A)+{ }^{5} C_{2} \) \( (\operatorname{adj} A)^{2}-\ldots-{ }^{5} C_{5}(\operatorname{adj} A)^{5} \), then the sum of all elements of the matrix B is:

Answer 1

 Given A = \(\begin{bmatrix} 2 &-1 \\[0.3em] 0 & 2 \end{bmatrix}\)

∴ Modulus of sum of all elements of matrix B = |–1 –5 – 1| = –7.