The trajectory of a weather balloon, lAl_AlA, and a monitoring drone, lBl_BlB, are modeled as lines in 3D space relative to a fixed ground station at the origin OOO. The equations of the paths are given by:
lA:r=(1−12)+λ(213) l_A : \mathbf{r} = \begin{pmatrix} 1 \\ -1 \\ 2 \end{pmatrix} + \lambda \begin{pmatrix} 2 \\ 1 \\ 3 \end{pmatrix} lA:r=1−12+λ213 lB:r=(50−3)+μ(1−2k) l_B : \mathbf{r} = \begin{pmatrix} 5 \\ 0 \\ -3 \end{pmatrix} + \mu \begin{pmatrix} 1 \\ -2 \\ k \end{pmatrix} lB:r=50−3+μ1−2kwhere λ\lambdaλ and μ\muμ are scalar parameters and kkk is a constant.
Show that for all values of k≠−26k \neq -26k=−26, the paths lAl_AlA and lBl_BlB are skew.
197 exam-style questions on OCR A Level Maths 1.10 Vectors, covering 1.10.1 Vectors in two dimensions, 1.10.2 Vectors in three dimensions (A-level only), 1.10.3 Magnitude and direction of vectors, 1.10.4 Basic operations on vectors, 1.10.5 Position vectors, 1.10.6 Distance between points, 1.10.7 Problem solving using vectors, 1.10.8 Vectors in kinematics, and 1.10 Vectors. Each one has a worked solution and a mark scheme showing where the marks go.