Question

Represente explicitamente a matriz A=(aij) 2 X 3 tal que aij = 5i - j

Answer 1

$A=\left[\begin{array}{ccc}A11&A12&A13\\A21&A22&A23\end{array}\right]$

Aij = 5. i - j                   ( i= linha / j= coluna ) 
a11= 5.1-1 = 4
a12= 5.1-2 = 3
a13= 5.1-3 = 2
a21= 5.2-1 = 9
a22= 5.2-2 = 8
a23= 5.2-3 = 7

$A=\left[\begin{array}{ccc}4&3&2\\9&8&7\end{array}\right]$