Given that a = (-1,16,-1) and b = (-18,-15,-15),
find the unit vector which is perpendicular to the plane containing a and b.
There are two possible answers. Choose the answer with a positive x component.
(a*b) = (a2*b3-a3*b2)i - (a1*b3-a3*b1)j - (a1*b2-a2*b1)k
(a*b)/(|a*b|) = unit vector
The Attempt at a Solution
using the above formula i worked out (a*b)= -255i + 3j - 303K
the modulus of a*b is therefore: sqrt(2552 + 32 + 3032)
i then put these values into the equation and i get:
-0.6438i + 0.008j - 0.7651k
since i need to make it positive in the x component my final answer is:
0.644i + 0.008 - 0.765k
am i doing this correctly? it just seems like a very unusual numbers