### Mathematics Class XI

Unit-I: Sets and Functions
Chapter 1: Sets
Unit-II: Algebra
Chapter 5: Binomial Theorem
Chapter 6: Sequence and Series
Unit-III: Coordinate Geometry
Chapter 1: Straight Lines
Chapter 2: Conic Sections
Unit-IV: Calculus
Unit-V: Mathematical Reasoning
Unit-VI: Statistics and Probability
Chapter 1: Statistics
Chapter 2: Probability

# Rectangle Cartesian coordinates in space  are mutually perpendicular line in space. ( -axes)  -axes are called coordinate axes.  is called origin. The coordinate of is . The planes containing the pairs of intersecting lines are called coordinate planes named respectively as -planes. The -axes are respectively perpendicular to -planes. The system of axes thus obtained is known as rectangular or orthogonal system of coordinate axes.

Note:  are called the non-negative -axes and are non-positive -axes respectively. The above system of coordinates is known as the Rectangular Cartesian Coordinate System, named after the French mathematician Rene Descartes (1596-1650).

The octants:

The three coordinate planes, intersecting at origin divide the set of points not living on any of the coordinate planes into eight disjoint convex sets known as Octants.

A three dimensional space with , we can describe the eight octants as follows:

1. 2. 3. 4. 5. 6. 7. 8. Scroll to Top