Question

Find the direction ratios and direction cosines of the line joining the points (–4, 1, 7), (2, –3, 2).

Answer 1

Let A(–4, 1, 7), B(2, –3, 2)

Direction ratio’s of bar AB are (2 + 4, –3 – 1, 2 – 7) = (6, –4, –5) = (–6, 4, 5)

Direction cosines of AB are