Question

Find the unit vector perpendicular to each of the vector (a+b)and(a-b)where
a=i^+j^+k^' b=i^+2j^+3k^

Answer 1

a+b = 2i+3j+4K a-b = -j-2k Vector perpendicular to a+b and a-b is a cross b which is -2i+4j-2k Unit vector will be -2i+4j-2k/square root (24).