JEE Main & Advanced
Mathematics
Three Dimensional Geometry
Question Bank
Critical Thinking
question_answer
The distance between two points P and Q is d and the length of their projections of PQ on the co-ordinate planes are \[{{d}_{1}},{{d}_{2}},{{d}_{3}}\]. Then \[d_{1}^{2}+d_{2}^{2}+d_{3}^{2}=k{{d}^{2}}\] where . k- is