Question 1311

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

Question

The plane p{p} passes through the points with coordinates (6,0,2),{\left( 6, 0, 2 \right),} (5,1,5){\left( - 5, - 1, - 5 \right)} (1,3,7).{\left( - 1, 3, - 7 \right).}
(i)
Find a cartesian equation of p.{p.}
[4]
The line l1{l_1} has equation
x+92=y+52=z+3\frac{x + 9}{-2} = \frac{y + 5}{-2} = z + 3
and the line l2{l_2} has equation
x+132=y+35=z+7k,\frac{x + 13}{- 2} = \frac{y + 3}{- 5} = \frac{z + 7}{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