JEE Main 2023 · 25 January · Morning Shift · Mathematics · Three Dimensional Geometry
The distance of the point P(4, 6, - 2) from the line passing...
The distance of the point $P(4,6,−2) from thelinepassingthroughthepoint(−3,2,3)andparalleltoalinewithdirectionratios3, 3, - 1$ is equal to:
Options
A3
B6
C23
D14
Correct answer
D. 14
Step-by-step solution
The equation of line passing through the point (−3,2,3) and parallel to a line with direction ratios 3,3,−1 will be,
3x+3=3y−2=−1z−3=λ
Now let any point on the line will be, M(3λ−3,3λ+2,3−λ)</p><p>Weknowthedirectionratiosofthelinejoiningthepoints(x1,y1,z1)and(x2,y2,z2)isgivenby</p><p>(x2−x1,y2−y1,z2−z1)</p><p>Therefore,thedirectionratiosoflinePM,</p><p>D.RofPM \left(3\lambda - 7, 3\lambda - 4, 5 - \lambda\right)</p><p>Since,PMisperpendiculartotheline</p><p>⇒ 3\left(3\lambda - 7\right) + 3\left(3\lambda - 4\right) - 1\left(5 - \lambda\right) = 0</p><p>⇒ \lambda = 2</p><p>⇒ M\left(3, 8, 1\right)
Now distanceofpointPfrompointM,</p><p>⇒PM=(3−4)2+(8−6)2+(1+2)2</p><p>⇒ PM = \sqrt{14}</p>