Question

Find u · v.u = 6i − 4jv = i − j

Answer 1

$\begin{gathered} u=6i-4j \\ v=i-j \\ u\cdot v=(6i-4j)\cdot(i-j) \\ u\cdot v=6(i\cdot i)+4(j\cdot j) \\ u\cdot v=6+4 \\ u\cdot v=10 \end{gathered}$