4.1

Question 1

What size $A$ must have for the multiplication to be possible ?
$A \begin{pmatrix} a & b \\ c & d \\ e & f \\ g & h \\ \end{pmatrix}$

$n\times4$

$4\times4$

$1\times4$

Question 2

What is the size of $C$ ?
$C= \begin{pmatrix} a & b & c \\ d & d & f \\ g & h & i \\ j & k & l \\ m & n & o \\ \end{pmatrix} \begin{pmatrix} p & q \\ r & s \\ t & u \\ \end{pmatrix}$

$m\times 2$

$5\times 5$

$n\times k$

$5\times 2$

Question 3

What is $C$ equal to ?
$C = 2\begin{pmatrix} 1 & 2 & -1 \\ -8 & -4 & 2 \\ \end{pmatrix} - \begin{pmatrix} 4 & -2 & -1 \\ -1 & -1 & 0 \\ \end{pmatrix}$

$\left( \begin{smallmatrix} -2 & 6 & -1 \\ -15 & -7 & 4 \end{smallmatrix} \right)$

$\left( \begin{smallmatrix} 0 & -4 & -2 \\ -5 & 0 & -9 \end{smallmatrix} \right)$

$\left( \begin{smallmatrix} 0 & 6 & 0 \\ 3 & -2 & -3 \end{smallmatrix} \right)$

$\left( \begin{smallmatrix} 11 & 9 & 3 \\ -3 & 5 & 12 \end{smallmatrix} \right)$

Question 4

How is the matrix $E$ called ?
$F = E + F$

null matrix

diagonal matrix

orthogonal matrix

identity matrix

Question 5

Which equation is equivalent to this one ?
$A+B = C$

$T(A + B)=CT$

$(A + BT)=CT$

$AT + BT=CT$

$TA + B=CT$

Question 6

What is $L$ equal to ?
$L = \begin{pmatrix} -5 \\ -3 \\ 5 \\ \end{pmatrix} \begin{pmatrix} 0 & -2 & 4 \end{pmatrix}$

$\left( \begin{smallmatrix} 0 & 6 & 20 \end{smallmatrix} \right)$

$\left( \begin{smallmatrix} 0 & 10 & -20 \\ 0 & 6 & -12 \\ 0 & -10 & 20 \end{smallmatrix} \right)$

$\left( \begin{smallmatrix} 0 & 0 & 0 \\ 0 & 6 & 0 \\ 0 & 0 & 20 \end{smallmatrix} \right)$

$\{\}$