[tex]\displaystyle\\
\text{\bf Se da: } \\\\
\text{Vectorii }~\overrightarrow{u};~\overrightarrow{v} \\\\
\overrightarrow{u}\cdot \overrightarrow{v} =7\\\\
\Big|\overrightarrow{u}\Big|=3\\\\
\Big|\overrightarrow{v}\Big|=4\\\\
\text{\bf Se cere:}\\\\
\cos(\sphericalangle(\overrightarrow{u};~\overrightarrow{v}) )
[/tex]
[tex]\displaystyle\\
\text{\bf Rezolvare:} \\\\
\text{Folosim formula: }~ \overrightarrow{u}\cdot \overrightarrow{v} =
\Big|\overrightarrow{u}\Big|\cdot \Big|\overrightarrow{v}\Big|\cdot
\cos(\sphericalangle(\overrightarrow{u};~\overrightarrow{v}) ) \\\\\\
7=3\cdot 4 \cdot \cos(\sphericalangle(\overrightarrow{u};~\overrightarrow{v}) )\\\\
\cos(\sphericalangle(\overrightarrow{u};~\overrightarrow{v}) )= \frac{7}{3\cdot 4}= \boxed{\bf \frac{7}{12}}
[/tex]
