\(\vec{u} . (\vec{w} + \vec{z}) < 0\)
VRAI
FAUX
On a \(\vec{u}(4 ; 0)\), \(\vec{w}(1 ; -3)\) et \(\vec{z}(2 ; 1)\).
\(\vec{u} . (\vec{w} + \vec{z}) = 4 \times (1 + 2) + 0 \times (-3 + 1) = 12 + 0 = 12\)
