Question

Show that the points A (2î + 3ĵ + 5k̂), B(î + 2ĵ + 3k̂) and C(7î – k̂) are collinear.

Answer 1

Here,

AB = (1 + 2)î + (2-3)ĵ + (3 – 5)k̂

= 3î – ĵ – 2k̂

BC = (7 – 1)î + (0 – 2)ĵ + (-1 – 3)k̂

= 6î – 2ĵ – 4k̂

AC =(7 + 2)î + (0-3)ĵ + (-1 – 5)k̂

= 9î – 3ĵ – 6k̂

Thus, the points A, B and C are collinear