## MathSofiya the vector $e_v$ is a unit vector of v I guess $\vec v=<3,-1>$ $||v||=\sqrt{9+1}=\sqrt{10}$ so $e_v=\frac{1}{||v||} \vec v=\left <\frac3{\sqrt{10}},\frac{-1}{\sqrt{10}}\right >$ one year ago one year ago

1. MathSofiya

How did I do?

2. experimentX

seems all right!!

3. MathSofiya

Thank you!

4. experimentX

hardly a probs :)