### Introduction to three Dimensional geometry

Check us out at http://www.tutorvista.com get a free tutoring demo. You have read in your earlier lessons that given a point in plane , it is possible to find two numbers, called its co-ordinates in the plane. Conversely, given any ordered pair ( x, y ) there corresponds a point in the plane whose co-ordinates are ( x, y ). Let a rubber ball be dropped vertically in a room. The point on the floor, where the ball strikes, can be uniquely determined with reference to axes, taken along the length and breadth of the room. However, when the ball bounces back vertically upward, the position of the ball in space at any moment can not be determined with reference to two axes considered earlier. At any instant, the position of ball can be uniquely determined if in addition, we also know the height of the ball above the floor. If the height of the ball above the floor is 2.5cm and the position of the point where it strikes the ground is given by (5, 4), one way of describing the position of ball in space is with the help of these three numbers ( 5, 4, 2.5 ) Thus, the position of a point ( or an article ) in space can be uniquely determined with the help of three numbers. In this lesson, we will discuss in details about the co-ordinate system and co-ordinates of a point in space , distance between two points in space, position of a point dividing the join of two points in a given ratio internally/externally and about the projection of a point / line in space.

Length:
01:02