Angle between two Planes
Calculates the angle between two Planes of equations A.x + B.y + C.z + D = 0 and a.x + b.y + c.z + d = 0.
`cos(theta)=|A*a+B*b+C*c|/(sqrt(A^2+B^2+C^2)*sqrt(a^2+b^2+c^2))`
Calculates the angle between two Planes of equations A.x + B.y + C.z + D = 0 and a.x + b.y + c.z + d = 0.
`cos(theta)=|A*a+B*b+C*c|/(sqrt(A^2+B^2+C^2)*sqrt(a^2+b^2+c^2))`