Question

a vector perpendicular to i^+ j^+k^ is

Answer 1

Answer:

(i + j + k) dot (A i + B j + C k) = zero

A + B + C = 0       taking the dot product

A =1, B = 1, C = -2

Answer 2

Let a be vector ⊥ to i^ + j^ +k^

a=xi^+y j^ +z k^

⇒ a .( i^+ j^+k^)=0

⇒ x+y+z=0

x=3y=2j=−53+2−5=0.