Question

qual é a soma dos elementos da matriz C=(Cij)2x4' em que Cij=1+i-j​

Answer 1

$C~=~\left[\begin{array}{cccc}c_{11}&c_{12}&c_{13}&c_{14}\\c_{21}&c_{22}&c_{23}&c_{24}\end{array}\right] \\\\\\\\C~=~\left[\begin{array}{cccc}1+1-1&1+1-2&1+1-3&1+1-4\\1+2-1&1+2-2&1+2-3&1+2-4\end{array}\right] \\\\\\\\C~=~\left[\begin{array}{cccc}1&0&-1&-2\\2&1&0&-1\end{array}\right]$

Sendo assim, a soma dos elementos fica:

$Soma~=~1\,+\,0\,+\,(-1)\,+\,(-2)\,+\,2\,+\,1\,+\,0\,+\,(-1)\\\\\\Soma~=~1\,+\,0\,-\,1\,-\,2\,+\,2\,+\,1\,+\,0\,-\,1\\\\\\\boxed{Soma~=~0}$