The image of the point having position vector i¯+3j¯+4k¯ in the plane r¯.(2i¯−j¯+4k¯)+3=0
−3i¯+5j¯+k¯
−3i¯+5j¯+2k¯
3i¯+5j¯+k¯
3i¯+5j¯+2k¯
(x1,y1,z1)=(1,3,4) plane 2x−y+z+3=0
If (h,k,l) in the image of (x1,y1,z1)
⇒h−x1a=k−y1b=l−z1c
=−2(ax1+by1+cz1+d)a2+b2+c2