Class 12 RS Aggarwal Chapter-28 The Plane Solutions - Free PDF Download
FAQs on RS Aggarwal Class 12 Solutions Chapter-28 The Plane
1. Where can I find reliable, step-by-step solutions for all exercises in RS Aggarwal Class 12 Maths Chapter 28, The Plane?
Vedantu provides comprehensive, exercise-wise solutions for RS Aggarwal Class 12 Maths Chapter 28, The Plane. These solutions are crafted by subject-matter experts to align with the 2025-26 CBSE syllabus, ensuring every step is clearly explained for correct problem-solving and easy understanding.
2. What are the main types of problems solved in RS Aggarwal Class 12 Chapter 28 on The Plane?
The solutions for Chapter 28 guide you through solving a range of problem types, including:
- Finding the vector and Cartesian equations of a plane under various given conditions.
- Calculating the angle between two planes using their normal vectors.
- Determining the shortest distance of a point from a plane.
- Finding the equation of a plane that passes through the intersection of two other planes.
- Solving problems where a plane is parallel or perpendicular to a given line or another plane.
3. How do I solve for the equation of a plane that passes through three non-collinear points as per the RS Aggarwal method?
To find the equation of a plane passing through three non-collinear points A, B, and C with position vectors a, b, and c, you should follow these steps:
1. Determine two vectors that lie in the plane, for example, vector AB = (b - a) and vector AC = (c - a).
2. Calculate the normal vector (n) to the plane by computing the cross product of these two vectors: n = AB × AC.
3. The required equation of the plane is then given by the formula (r - a) · n = 0. This step-by-step method is clearly demonstrated in the solutions.
4. What is the key difference between the vector and Cartesian equations of a plane, and which one is better for solving problems?
The vector form (e.g., r · n = d) is powerful for conceptual problems involving direction and geometric relationships. The Cartesian form (ax + by + cz = d) is generally more convenient for algebraic calculations, such as finding intercepts or the distance of a point with specific coordinates. The best method depends on the information given in the problem; if the question provides vectors, use the vector form, and if it provides coordinates, the Cartesian form is usually more direct.
5. Why is the normal vector so crucial when solving problems related to planes in 3D geometry?
The normal vector is crucial because it defines the unique orientation of a plane in three-dimensional space. A plane has infinitely many vectors lying on it, but only one direction perpendicular to it. This perpendicular direction, represented by the normal vector, is the key to solving almost all problems related to planes, such as finding the angle between two planes (by using their normals), calculating the distance of a point from a plane, and establishing conditions for parallelism and perpendicularity.
6. How do the solutions explain the method for finding a plane that passes through the intersection of two other planes?
The solutions explain this using the 'family of planes' concept. If the equations of two intersecting planes are P₁ = 0 and P₂ = 0, then the equation of any plane passing through their line of intersection can be written as P₁ + λP₂ = 0, where λ is a constant. To find the exact equation, you use an additional condition given in the problem (like a point the plane passes through) to solve for the specific value of λ. This is a standard method in the RS Aggarwal textbook that simplifies the solving process.
7. What is a common mistake to avoid when calculating the shortest distance of a point from a plane?
A common mistake is incorrectly substituting the coordinates of the point into the plane's equation. The correct formula for the distance from a point (x₁, y₁, z₁) to the plane ax + by + cz + d = 0 is |ax₁ + by₁ + cz₁ + d| / √(a² + b² + c²). Students often forget to take the absolute value of the numerator or miscalculate the magnitude of the normal vector in the denominator. The provided solutions carefully demonstrate each step to help avoid these errors.

















