Target Exam

CUET

Subject

Section B1

Chapter

Determinants

Question:

Find $|AB|$, if $A = \begin{bmatrix} 0 & -1 \\ 0 & 2 \end{bmatrix}$ and $B = \begin{bmatrix} 3 & 5 \\ 0 & 0 \end{bmatrix}$.

Options:

0

2

4

6

Correct Answer:

0

Explanation:

The correct answer is Option (1) → 0 ##

Given $A = \begin{bmatrix} 0 & -1 \\ 0 & 2 \end{bmatrix}$ and $B = \begin{bmatrix} 3 & 5 \\ 0 & 0 \end{bmatrix}$

$∴AB = \begin{bmatrix} 0 & -1 \\ 0 & 2 \end{bmatrix} \begin{bmatrix} 3 & 5 \\ 0 & 0 \end{bmatrix}$

or $= \begin{bmatrix} 0+0 & 0+0 \\ 0+0 & 0+0 \end{bmatrix}$

or $ = \begin{bmatrix} 0 & 0 \\ 0 & 0 \end{bmatrix}$

Hence, $|AB| = 0$