Question

What is `||v||` if `v = < 3,1,-2 >`?

Answer 1

`sqrt(14)\approx 3.74166`

Explanation:

The length `||vec(v)||` of a 3-dimensional vector `\vec(v)=\langle a,b,c\rangle` is `sqrt(a^2+b^2+c^2)`.

Therefore if `vec(v)=\langle 3,1,-2\rangle`, then `||vec(v)||=sqrt{9+1+4}=sqrt(14)\approx 3.74166`