Sigma Percentile
JEE Main 2002
LEVELJEE Main

Animated Solution for Mathematics - Three Dimensional Geometry: A plane which passes through the point and the line is

Select Answer:

Visualized Solution

Visualizing the Setup

  • Given point:
  • Given line:
  • Objective: Find the equation of the plane containing both and .

The Standard Approach vs. The Trap

  • Usually, a point and a line define a unique plane.
  • But what if the point lies on the line?
  • Let's check the relationship between and .

Substituting into

  • Line equation:
  • Substitute :

Evaluating the Ratios

  • X-ratio:
  • Y-ratio:
  • Z-ratio:

The Point Lies on the Line!

  • Since all three ratios equal , the point satisfies the line equation.
  • Conclusion: lies on the line .

The Infinite Planes Concept

  • If a point lies on a line, they do not define a unique plane.
  • Instead, infinitely many planes can pass through that line (like pages of a book).

The Smart Strategy

  • Since there are infinite planes, we must check the given options.
  • The correct plane must contain the entire line .
  • A plane contains a line if it contains at least two points on that line.

Identifying a Second Point

  • We already have one point: .
  • From the line equation , we can extract the base point.
  • Base point .

Testing Option 1 with Point

  • Option 1:
  • Substitute :
  • (Satisfied!)

Testing Option 1 with Point

  • Option 1:
  • Substitute :
  • (Satisfied!)

Final Conclusion

  • Since the plane contains two distinct points of the line, it contains the entire line.
  • Therefore, Option 1 is the correct answer.

The Sigma Insight: Equation of a Plane

Solution Diagram

Analyzing the Setup

Imagine you are standing in the vast expanse of 3D space. You have a point and a line defined by the symmetric equations:
The standard, textbook approach is to find the normal vector of the plane by taking the cross product of the line's direction vector and the vector connecting the point to the line.
However, in the world of JEE Advanced, the most dangerous assumption is that the geometry is 'standard.' If the point is actually sitting right on the line , the line and the point would not define a unique plane. Instead, they would act like the spine of a book, with infinitely many planes passing through them.

The Investigation

Testing the Reality
Let us test our hypothesis by substituting the coordinates of into the line equation:
Calculating these ratios, we get:
The ratios are identical! This is a massive revelation: our point lies exactly on the line . We are not looking for a unique plane; we are looking for one specific plane out of an infinite family that contains this line.

The Strategy

The Power of Verification
Since we cannot derive a single equation from scratch, we must pivot. We know that the correct plane must contain the entire line .
A plane contains a line if and only if it contains at least two distinct points on that line. We already have point . We need a second point.
Looking at the line equation, we can easily extract the base point . Now, we simply test the options provided.

Final Verification

Let us check the option . Substituting , we get:
It works! Now, we must verify with point :
Both points satisfy the equation. Because this plane contains two distinct points of the line, it must contain the entire line itself.
The mystery is solved, not by brute-force calculation, but by conceptual insight and strategic verification. Keep this in your toolkit: always check if your point lies on the line before you start your cross products!

Similar Questions

JEE Main 2015
LEVELJEE Advanced

The equation of the plane containing the line ; , and parallel to the plane, , is:

(A)
(B)
(C)
(D)
JEE Main 2021 (24 February Shift 1)
LEVELJEE Main

The equation of the plane passing through the point and perpendicular to the planes and , is:

(A)
(B)
(C)
(D)
JEE Advanced 2016
LEVELJEE Main

Let be the image of the point with respect to the plane . Then the equation of the plane passing through and containing the straight line is

(A)
(B)
(C)
(D)
JEE Advanced 2005
LEVELJEE Advanced

Find the equation of the plane containing the line and at a distance of from the point .

JEE Main 2019 (8 April Shift 1)
LEVELBoard

The equation of a plane containing the line of intersection of the planes and and passing through the point is :

(A)
(B)
(C)
(D)
JEE Advanced 2010
LEVELJEE Advanced

Equation of the plane containing the straight line and perpendicular to the plane containing the straight lines and is

(A)
(B)
(C)
(D)
JEE Main 2019 (9 January)
LEVELJEE Advanced

The equation of the plane containing the straight line and perpendicular to the plane containing the straight lines and is:

(A)
(B)
(C)
(D)
JEE Main 2019 (09 April Shift 1)
LEVELJEE Main

A plane passing through the points and and making an angle with the plane , also passes through the point

(A)
(B)
(C)
(D)
JEE Main 2021 (31 Aug Shift 1)
LEVELJEE Main

Let the equation of the plane, that passes through the point and contains the line of intersection of the planes and , be , then is equal to :

(A)
(B)
(C)
(D)
JEE Main 2019 (10 January Shift 1)
LEVELJEE Main

The plane passing through the point (4, -1, 2) and parallel to the lines and also passes through the point :

(A)
(-1, -1, -1)
(B)
(-1, -1, 1)
(C)
(1, 1, -1)
(D)
(1, 1, 1)