Maths Class 11 Chapter 12. Introduction to 3 D Geometry | Page 4

Coordinates of a Point in Space
Having chosen a fixed 3D coordinate system in the space , we can associate a given point in the space using three coordinates ( x , y , z ) and conversely , given a triplet of three numbers ( x , y , z ), how , we locate a point in the space .
Distance between 2 points
Numerical : Find the distance between the points P ( 1 , – 3 , 4 ) and Q (– 4 , 1 , 2 )
Solution :
PQ = √ (( -4-1 ) 2 + ( 1- ( -3 )) 2 + ( 2-4 ) 2 ) = 3 √5 units .