JEE MainMathematicsThree Dimensional Geometry
Let Q be the image of the point P(3, 1, 5) in the line x 1 = y -1 = z 2 . The square of the perpendicular distance of the point Q from the plane x - 2y + 2z - 8 = 0 is _________
Correct answer
9
Step-by-step solution
Let M be the foot of the perpendicular drawn from the point P(3, 1, 5) to the given line. Any general point on the line x 1 = y -1 = z 2 = is given by M( , - , 2 ) . The direction ratios of the line segment PM are ( - 3, - - 1, 2 - 5) . Since PM is perpendicular to the given line, the dot product of their direction ratios is zero: 1( - 3) - 1(- - 1) + 2(2 - 5) = 0 - 3 + + 1 + 4 - 10 = 0 6 - 12 = 0 = 2 Thus, the foot of the perpendicular is M(2, -2, 4) . Since M is the midpoint of the line segment joining P and its