If $$A = \left(\begin{array}{c}1 & 0\\ -1 & 1\end{array}\right)$$, then $$A^{50}$$ is
Given $$A = \left(\begin{array}{c}1 & 0\\ -1 & 1\end{array}\right)$$, then $$A^{50}$$
$$\ A^2$$= $$\begin{bmatrix}1 & 0\\ -1 &1 \end{bmatrix}.\begin{bmatrix}1 & 0\\ -1 &1 \end{bmatrix}$$
=$$\begin{bmatrix}(1)(1)+0(-1) & 1(0)+0(1)\\ (1)(-1)+(1)(-1) &(-1)(0)+(1)(1) \end{bmatrix}$$
=$$\begin{bmatrix}1 & 0\\ -2 &1 \end{bmatrix}$$.
Now, $$\ A^3$$= $$\begin{bmatrix}1 & 0\\ -2 &1 \end{bmatrix}.\begin{bmatrix}1 & 0\\ -1 &1 \end{bmatrix}$$
=$$\begin{bmatrix}(1)(1)+0(-1) & 1(0)+0(1)\\ (1)(-2)+(1)(-1) &(-2)(0)+(1)(1) \end{bmatrix}$$
=$$\begin{bmatrix}1 & 0\\ -3 &1 \end{bmatrix}$$.
So, in general $$\ A^n$$= $$\begin{bmatrix}1 & 0\\ -n &1 \end{bmatrix}$$.
Therefore, $$\ A^{50}$$= $$\begin{bmatrix}1 & 0\\ -50 &1 \end{bmatrix}$$, which is given in Option C
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