Question 1311

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

Question

The plane p{p} passes through the points with coordinates (3,7,3),{\left( 3, 7, - 3 \right),} (1,1,5){\left( 1, - 1, 5 \right)} (5,5,1).{\left( - 5, - 5, - 1 \right).}
(i)
Find a cartesian equation of p.{p.}
[4]
The line l1{l_1} has equation
x82=y72=z7\frac{x - 8}{2} = \frac{y - 7}{2} = z - 7
and the line l2{l_2} has equation
x106=y227=z9k,\frac{x - 10}{6} = \frac{y - 22}{- 7} = \frac{z - 9}{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