Question

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4)Sendo A= 1 -1 -2 2 e B= 2 5 1 -1. Determine o valor de B×A


5)Sendo A = 2 4 -1 2 3 6 e B=3 0. Determine o produto de A×B

Answer 1

Explicação passo-a-passo:

5)

$\sf B\times A=\left[\begin{array}{cc} \sf 2 & \sf 5 \\ \sf 1 & \sf -1 \end{array}\right]\times\left[\begin{array}{cc} \sf 1 & \sf -1 \\ \sf -2 & \sf 2 \end{array}\right]$

$\sf B\times A=\left[\begin{array}{cc} \sf 2\cdot1+5\cdot(-2) & \sf 2\cdot(-1)+5\cdot2 \\ \sf 1\cdot1+(-1)\cdot(-2) & \sf 1\cdot(-1)+(-1)\cdot2 \end{array}\right]$

$\sf B\times A=\left[\begin{array}{cc} \sf 2-10 & \sf -2+10 \\ \sf 1+2 & \sf -1-2 \end{array}\right]$

$\sf B\times A=\left[\begin{array}{cc} \sf -8 & \sf 8 \\ \sf 3 & \sf -3 \end{array}\right]$

6)

$\sf A\times B=\left[\begin{array}{cc} \sf 2 & \sf 4 \\ \sf -1 & \sf 2 \\ \sf 3 & \sf 6 \end{array}\right]\times\left[\begin{array}{c} \sf 3 \\ \sf 0 \end{array}\right]$

$\sf A\times B=\left[\begin{array}{c} \sf 2\cdot3+4\cdot0 \\ \sf -1\cdot3+2\cdot0 \\ \sf 3\cdot3+6\cdot0 \end{array}\right]$

$\sf A\times B=\left[\begin{array}{c} \sf 6+0 \\ \sf -3+0 \\ \sf 9+0 \end{array}\right]$

$\sf A\times B=\left[\begin{array}{c} \sf 6 \\ \sf -3 \\ \sf 9 \end{array}\right]$