If $A=\begin{bmatrix}1 & 2 \\a & -1 \end{bmatrix}$ and $A^{2}=\begin{bmatrix}0 & 0 \\0 & 0 \end{bmatrix}$ then the values of a is

E

Editor

Sep 18, 2022

If $A=\begin{bmatrix}1 & 2 \\a & -1 \end{bmatrix}$ and $A^{2}=\begin{bmatrix}0 & 0 \\0 & 0 \end{bmatrix}$ then the values of a is

Difficulty: Easy

A:

-1

B:

1/2

C:

-1/2

D:

2

ID: 63273dbaca83163ac3a11bbf