Question

If equation lx + my + nz = p is normal form of a plane, then which of the following is not true : 

(a) l, m, n are direction cosines of normal to the plane 

(b) p is perpendicular distance from origin to plane 

(c) for every value of p, plane passes through origin 

(d) l² + m² + n² = 1

Answer 1

Answer is (c)

∵ P is distance of the plane from origin. 

So, plane can pass through origin only if p = 0 otherwise not for other values.