Question

vreau si eu la 5 va roog

Answer 1

$\displaystyle\\ \overrightarrow{AB}+\overrightarrow{BC}=\overrightarrow{AC}~~~\text{Conform relatiei lui {\it Chasles}}\\\\ \Longrightarrow~~~\overrightarrow{AC}=\overrightarrow{AB}+\overrightarrow{BC}=2i+2j ~~+~~2i+j = \boxed{4i+3j}\\\\ \text{Lungimea lui }\overrightarrow{AC} = \Big|\overrightarrow{AC}\Big| =\Big|4i+3j\Big|\\\\ \Big|4i+3j\Big|=\sqrt{4^2 + 3^2}=\sqrt{16 + 9}= \sqrt{25}=\boxed{\bf 5}$