If \(A = \begin{pmatrix} 2 & 1 \\ 2 & 3 \\ 1 & 2... | JAMB UTME - Mathematics - 2022

Question 1 Report

If $A = \begin{pmatrix} 2 & 1 \\ 2 & 3 \\ 1 & 2 \end{pmatrix}$ and $B = \begin{pmatrix} 3 & 2 \\ 4 & 2 \end{pmatrix}$. Find $AB$

(\begin{matrix} 18 & 6 \\ 12 & 10 \\ 10 & 6 \end{matrix})

(\begin{matrix} 18 & 6 \\ 12 & 10 \\ 10 & 6 \end{matrix})

(\begin{matrix} 18 & 6 \\ 12 & 10 \\ 10 & 6 \end{matrix})

(\begin{matrix} 18 & 6 \\ 12 & 10 \\ 10 & 6 \end{matrix})

Answer Details

Given A = $(\begin{matrix} 2 & 1 \\ 2 & 3 \\ 1 & 2 \end{matrix})$ and B = $(\begin{matrix} 3 & 2 \\ 4 & 2 \end{matrix})$

We can multiply these matrices since the number of colums in A = number of rows in B

AB = $(\begin{matrix} (2 * 3) + (1 * 4) & (2 * 2) + (1 * 2) \\ (2 * 3) + (3 * 4) & (2 * 2) + (3 * 2) \\ (1 * 3) + (2 * 4) & (1 * 2) + (2 * 2) \end{matrix})$

AB = $(\begin{matrix} (6 + 4) & (4 + 2) \\ (6 + 12) & (4 + 6) \\ (3 + 8) & (2 + 4) \end{matrix})$

= $(\begin{matrix} 10 & 6 \\ 18 & 10 \\ 11 & 6 \end{matrix})$

$(\begin{matrix} (2 * 3) + (1 * 4) & (2 * 2) + (1 * 2) \\ (2 * 3) + (3 * 4) & (2 * 2) + (3 * 2) \\ (1 * 3) + (2 * 4) & (1 * 2) + (2 * 2) \end{matrix})$

$(\begin{matrix} 3 & 2 \\ 4 & 2 \end{matrix})$

Read lesson note on Matrices And Determinants (JAMB)

Matrices And Determinants

View Answer

If \(A = \begin{pmatrix} 2 & 1 \\ 2 & 3 \\ 1 & 2 \end{pmatrix}\) and \(B = \begin{pmatrix} 3 & 2 \\ 4 & 2 \end{pmatrix}\). Find \(AB\)

Download The App On Google Playstore

If \(A = \begin{pmatrix} 2 & 1 \\ 2 & 3 \\ 1 & 2 \end{pmatrix}\) and \(B = \begin{pmatrix} 3 & 2 \\ 4 & 2 \end{pmatrix}\). Find \(AB\)

Related Questions

Download The App On Google Playstore