Three Dimensional Geometry
Class 12 Mathematics • Chapter 11
Session 2025-26
Rationalised Syllabus Alert:
The entire topic of “Plane” (Equation of planes, Angle between planes, Distance of a point from a plane) has been removed. The chapter now focuses exclusively on Lines in Space.
The Rectangular Coordinate System in Space (Octants)
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Exercise 11.1
Direction Cosines (l, m, n) and Direction Ratios of a Line.
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Exercise 11.2
Equation of a Line in Space, Angle between Two Lines, and Shortest Distance between Skew Lines.
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Miscellaneous Exercise
Comprehensive problems on Direction Cosines and Lines involving vector and cartesian forms.
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