Find the direction cosines of the unit vector perpendicular to the plane + 1 = 0 passing through the origin.

The given plane equation is

Now, we calculate the magnitude of the vector.

On dividing both sides of the plane equation by 7, we get

Recall that the equation of the plane in normal form is given by where is a unit vector perpendicular to the plane through the origin.

So, here

This is a unit vector normal to the plane.

Thus, the direction cosines of the unit vector perpendicular to the given plane are.