[tex]\vec{u}[/tex] and [tex]\vec{v}[/tex] are vectors and:
[tex]\vec{u}=14j=0i+14j=[0,14]\\\\
\vec{v}=i+4j=1i+4j=[1,4][/tex]
[tex]\vec{u}\cdot\vec{v}[/tex] is the dot product or scalar product, so:
[tex]\vec{u}\cdot\vec{v}=[0,14]\cdot[1,4]=0\cdot1+14\cdot4=56[/tex]
Correct answer is A.
