Complete the multiplication: AB

Question

asked Sep 25, 2018 176k views

1 Answer

VeeTheSecond · Answer 1 · 2018-09-30T20:48:54+0000

Option: B is the correct answer.

$B.\ \left[\begin{array}{ccc}6&24\\3.4&13\end{array}\right]$

We are given two matrices A and B as follows:

$A=\left[\begin{array}{ccc}3&0\\2&-1\end{array}\right]$

and

$B=\left[\begin{array}{ccc}2&8\\0.6&3\end{array}\right]$

We know that the multiplication of two matrices of the type:

$A=\left[\begin{array}{ccc}a&b\\c&d\end{array}\right]$

and

$B=\left[\begin{array}{ccc}a'&b'\\c'&d'\end{array}\right]$

is given by:

$AB=\left[\begin{array}{ccc}aa'+bc'&ab'+bd'\\ca'+dc'&cb'+dd'\end{array}\right]$

Hence, here we have:

$AB=\left[\begin{array}{ccc}3* 2+0* 0.6&3* 8+0* 3\\2* 2+(-1)* 0.6&2* 8+(-1)* 3\end{array}\right]$

i.e.

$AB=\left[\begin{array}{ccc}6+0&24+0\\4-0.6&16-3\end{array}\right]$

i.e.

$AB=\left[\begin{array}{ccc}6&24\\3.4&13\end{array}\right]$