Question

If the vectors `2 hat i - 3 hat j + 4 hat k` and `p hat i + 6 hat j - 8 hat k` are collinear, then find the value of p.

Answer 1

`2 hat i - 3 hat j + 4 hat k` and `p hat i + 6 hat j - 8 hat k` are collinear.

∴ The coefficients of `hat i, hat j , hat k` are proportional.

∴ `2/p = (-3)/6`

= `4/(-8)`

`2/p = (-1)/2`

2 × 2 = −p

4 = −p

∴ p = −4

Therefore, the value of p for the vectors to be collinear is −4.