find a vector in the direction 2i+j-2k that has length 1

Question

amistre64 · Answer

how long is the given vector to begin with?

amistre64 · Answer

vector = L units

to determine the vector of 1 unit, divide both sides by L

vector/L = L/L units

vector/L = 1 units

anonymous · Answer

we just have the direction and the length of the required vector

amistre64 · Answer

thats all we need, and some knowledge about what a unit vector is spose to be ....

anonymous · Answer

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?

amistre64 · Answer

thats correct :)  except maybe check you length again

anonymous · Answer

and use the length 1 multiply to the unit vector to get what we need, is it right?

amistre64 · Answer

sqrt(8) = 2sqrt(2)

amistre64 · Answer

ugh ... 4+1+4 = 9 so sqrt(9) = 3

anonymous · Answer

yeah, you are right, my bad. thanks a lot

amistre64 · Answer

divide all the vector parts by 3 :)