QCM 6
Si
\(\begin{cases}(\vec{u},\vec{v})= \frac{5\pi}{6}\\(\vec{v},\vec{w})= \frac{2\pi}{3}\\(\vec{w},\vec{t})= \frac{\pi}{2}\end{cases}\)
alors \((\vec{u},\vec{t})=0\)
Votre choixChoix attenduRéponse
\((\vec{u},\vec{t})=(\vec{u},\vec{v})+(\vec{v},\vec{w})+(\vec{w},\vec{t})\)
\(\iff (\vec{u},\vec{t})= \frac{5\pi}{6}+\frac{2\pi}{3}+\frac{\pi}{2}\)
\(\iff (\vec{u},\vec{t})= \frac{5\pi}{6}+\frac{4\pi}{6}+\frac{3\pi}{6}\)
\(\iff (\vec{u},\vec{t})= \frac{12\pi}{6}=2\pi=0\)
