Given :

Equation of plane : 3x + 4 = 0

To Find : Direction cosines of the normal i.e.

Formula :

1) Direction cosines :

If a, b & c are direction ratios of the vector then its direction cosines are given by

Answer :

For the given equation of plane

-3x = 4

Direction ratios of normal vector are (-3, 0, 0)

= 3

Therefore, direction cosines are