[tex]\bf \begin{cases}
u=-4i+1j\implies & \ \textless \ -4,1\ \textgreater \ \\
v=4i+1j\implies &\ \textless \ 4,1\ \textgreater \
\end{cases}\qquad u+v\implies \ \textless \ -4,1\ \textgreater \ +\ \textless \ 4,1\ \textgreater \
\\\\\\
\ \textless \ -4+4~,~1+1\ \textgreater \ \implies \ \textless \ 0,2\ \textgreater \ \\\\
-------------------------------\\\\
\stackrel{magnitude}{||u+v||}\implies \sqrt{0^2+2^2}\implies 2[/tex]
