Question 1311

Vectors II: Lines and Planes
2011 Paper 1 Question 11 Variant

Question

The plane p{p} passes through the points with coordinates (2,2,1),{\left( - 2, 2, - 1 \right),} (0,6,1){\left( 0, - 6, 1 \right)} (1,8,2).{\left( 1, - 8, 2 \right).}
(i)
Find a cartesian equation of p.{p.}
[4]
The line l1{l_1} has equation
x+45=y5=z+35\frac{x + 4}{5} = y - 5 = \frac{z + 3}{5}
and the line l2{l_2} has equation
x231=y5=z18k,\frac{x - 23}{1} = \frac{y}{- 5} = \frac{z - 18}{k},
where k{k} is a constant. It is given that l1{l_1} and l2{l_2} intersect.
(ii)
Find the value of k.{k.}
[4]
(iii)
Show that l1{l_1} lies in p{p} and find the coordinates of the point at which l2{l_2} intersects p.{p.}
[4]
(iv)
Find the acute angle between l2{l_2} and p.{p.}
[3]

Answer