The unit vector is given by: u = v / lvl The module of v is: lvl = root ((4) ^ 2 + (-8) ^ 2) lvl = root (16 + 64) lvl = root (80) lvl = 4 * root (5) Substituting: u = 4i-8j / (4 * root (5)) Rewriting: u = i-2j / root (5) u = root (5) / 5 i - 2 * root (5) / 5 j Answer: The unit vector in the direction of v is: d. sqrt5 / 5 i - 2 sqrt5 / 5 j
