Question

A=(aij)3×3tal que aij= i+2j

Answer 1

A = (aij)3x3

$\left[\begin{array}{ccc}a11&a12&a13\\a21&a22&a23\\a31&a32&a33\end{array}\right]$

aij = i + 2j

a11 = 1 + 2.(1) => a11 = 1 + 2 => a11 = 3
a12 = 1 + 2.(2) => a12 = 1 + 4 => a12 = 5
a13 = 1 + 2.(3) => a13 = 1 + 6 => a13 = 7

a21 = 2 + 2.(1) => a21 = 2 + 2 => a21 = 4
a22 = 2 + 2.(2) => a22 = 2 + 4 => a22 = 6
a23 = 2 + 2.(3) => a23 = 2 + 6 => a23 = 8

a31 = 3 + 3.(1) => a31 = 3 + 3 => a31 = 6
a32 = 3 + 3.(2) => a32 = 3 + 6 => a32 = 9
a33 = 3 + 3.(3) => a33 = 3 + 9 => a33 = 12

$\left[\begin{array}{ccc}3&5&7\\4&6&8\\6&9&12\end{array}\right]$