Please solve RD Sharma Class 12 Chapter 26 Directions Cosines and Direction Ratio Exercise Multiple Choice Question, question 5 Maths textbook solution.
Answer: (b) Externally in ratio 2:3
Hint: Use section formula
Given: Point(-1,3,4) and (2,-5,6)
To Find: Ratio in which xy plane divide the points
Solution:
Suppose xy plane divide the line segment joining the points O(-1,3,4) and Q(2,-5,6) in ratio k:1
Using section formula coordinates of the point of intersection are
The z-coordinate of any point of the xy-plane is zero.
Therefore, the xy plane divide the given points in 2:3 externally. Hence option(b) externally in the ratio 2:3 is correct.