Given that the point A A\,A has position vector −4i+8j−3k-4\mathbf{i} + 8\mathbf{j} - 3\mathbf{k}−4i+8j−3k and the point B B\,B has position vector −9i+2j−k-9\mathbf{i} + 2\mathbf{j} - \mathbf{k}−9i+2j−k
Find ∣AB⃗∣|\vec{AB}|∣AB∣, giving your answer in exact form.
309 exam-style questions on Edexcel A Level Maths Vectors, covering 12.1 3D Coordinates, 12.2 Vectors in 3D, 12.3 Solving Geometric Problems, and 12.4 Application to Mechanics. Each one has a worked solution and a mark scheme showing where the marks go.