Skip to content
MathsGenie logo
Open app

Course home

  1. A Level
  2. Maths WJEC
  3. Question bank

Vectors

EasyMediumHard
12345678910111213141516171819202122232425262728293031323334353637383940414243
Question 26

Two laser guidance beams used in a large-scale precision engineering project are modelled as lines l1 l_1\,l1​ and l2 l_2\,l2​ relative to a fixed origin OOO. The equations of the lines are given by:

l1:r=(i+kj)+t(i−2j+2k) l_1: \mathbf{r} = (\mathbf{i} + k\mathbf{j}) + t(\mathbf{i} - 2\mathbf{j} + 2\mathbf{k}) l1​:r=(i+kj)+t(i−2j+2k) l2:r=(i+4j+6k)+s(2i+j−2k) l_2: \mathbf{r} = (\mathbf{i} + 4\mathbf{j} + 6\mathbf{k}) + s(2\mathbf{i} + \mathbf{j} - 2\mathbf{k}) l2​:r=(i+4j+6k)+s(2i+j−2k)

where t t\,t and s s\,s are scalar parameters and k k\,k is a constant.

Given that the two laser beams intersect at a single point:

a.

find the value of kkk.

[3]
b.

find the position vector of the point of intersection.

[1]
c.

Calculate the acute angle between l1 l_1\,l1​ and l2l_2l2​. Give your answer in degrees to one decimal place.

[3]
d.

The point A A\,A lies on l1 l_1\,l1​ with parameter t=4t = 4t=4. The point B B\,B lies on l2 l_2\,l2​ such that the vector AB⃗\vec{AB}AB is perpendicular to l2l_2l2​.

Find the coordinates of BBB.

[4]

Vectors Questions

  1. A Level
  2. /Maths
  3. /Vectors