Question

Determine a soma dos elementos da 3° coluna da matriz A= (aij) 3×3 tal que aij= 4+3 i-j

Answer 1

Se $aij = 4+3.i - j$

$a11 = 4+3.1-1 = 6 \\ a12= 4+3.1-2= 5 \\ a13= 4+3.1-3= 4 \\ a21= 4+3.2-1= 9\\ a22= 4+3.2-2= 8\\ a23= 4+3.2-3=7\\ a31= 4+3.3-1= 12\\ a32= 4+3.3-2= 11\\ a33= 4+3.3-3= 10$

$A= \left[\begin{array}{ccc}6&5&4\\9&8&7\\12&11&10\end{array}\right] \\ \\ 4+7+10= 21$