Zaymiey

📐 Mathematics  ·  Introduction to Three Dimensional Geometry  ·  JEE

The point which divides the join of (2, 1, 4) and (4, 3, 2) externally in the ratio 1 : 2 is:

Answer: (0, −1, 6).

  • A (0, −1, 6)
  • B (0, 1, 6)
  • C (6, 5, 0)
  • D (3, 2, 3)

Correct answer: A. (0, −1, 6)

Explanation: For external division replace n by −n: x = (1·4 − 2·2)/(1 − 2) = 0, y = (3 − 2)/(−1) = −1, z = (2 − 8)/(−1) = 6.

zxyOP(x, y, z)first octant:x>0, y>0, z>0

Concept context

Coordinate axes and planes in space, octants, distance between two points, and the section formula

Read the full Introduction to Three Dimensional Geometry notes →