Matrices and Determinants

MM

Mashaal Masha

Sep 28, 2022

Choose the correct options for the following questions.

The multiplicative inverse of matrix $A{A^{-1})$ is

Difficulty: Easy

A:

|A|/AdjA

B:

1/AdjA |A|

C:

1/|A| adj A

D:

-|A|

The adjoint of the matrix $A=\begin{bmatrix}a & b \\c & d \end{bmatrix}$ is

Difficulty: Easy

A:

\begin{bmatrix}-a & c \\b & -d \end{bmatrix}

B:

\begin{bmatrix}a & -c \\-b & d \end{bmatrix}

C:

\begin{bmatrix}1/a & -b \\-c & 1/d \end{bmatrix}

D:

\begin{bmatrix}-d & c \\b & -a\end{bmatrix}