JPJC Vectors Tutorial 1(a) Q1

JPJC Vectors Tutorial 1(a) Q1

7 marks
Tutorial
Free

The vectors \({\mathbf{a}}\), \({\mathbf{b}}\) and \({\mathbf{c}}\) are given by \(\mathbf{a}=3\mathbf{i}+4\mathbf{j}+5\mathbf{k}\), \(\mathbf{b}=-\mathbf{i}+\mathbf{j}-\mathbf{k}\), \(\mathbf{c}=2\mathbf{i}-\mathbf{j}+2\mathbf{k}\) respectively.

  1. Find the unit vector in the direction of \({\mathbf{a}}\).[1]
  2. Find the unit vectors parallel to \({\mathbf{b}}\).[2]
  3. Find the angle between the vectors \({\mathbf{b}}\) and \({\mathbf{c}}\), giving your answer to the nearest \(0.1{}^\circ \).[2]
  4. Find the vector of magnitude \(5\) in the direction of \({\mathbf{c}}\).[2]

Video Solution:

Default solution

  1. List item image
  2. List item image
  3. List item image
  4. List item image
Answer:(a) \(\dfrac1{5\sqrt2}\begin{pmatrix}3\\4\\5\end{pmatrix}\) (b) \(\pm\dfrac1{\sqrt3}\begin{pmatrix}-1\\1\\-1\end{pmatrix}\) (c) \(164.2^\circ\) (d) \(\dfrac53\begin{pmatrix}2\\-1\\2\end{pmatrix}\)

Need help? Join our JC Math tuition classes.

Learn more