Here's the question you clicked on:
Hoa
find a vector in the direction 2i+j-2k that has length 1
how long is the given vector to begin with?
vector = L units to determine the vector of 1 unit, divide both sides by L vector/L = L/L units vector/L = 1 units
we just have the direction and the length of the required vector
thats all we need, and some knowledge about what a unit vector is spose to be ....
i have idea like: unit vector of that direction is <2, 1, -2>/sqr(2^2 +1^2+(-2)^2 =<2/sqr(5,1/sqr(5),-2/sqr(5)> is is right?
thats correct :) except maybe check you length again
and use the length 1 multiply to the unit vector to get what we need, is it right?
ugh ... 4+1+4 = 9 so sqrt(9) = 3
yeah, you are right, my bad. thanks a lot
divide all the vector parts by 3 :)