1.21: Referred to a fixed origin the point A has position vector (4i and the point has

4PM1/2/June/2019 — Question 1 · 4 marks

Referred to a fixed origin O\displaystyle O, the point A\displaystyle A has position vector (4i+3j)\displaystyle (4\mathbf{i}+3\mathbf{j}) and the point B\displaystyle B has position vector (i+7j)\displaystyle (\mathbf{i}+7\mathbf{j}).
(a) Find AB→\displaystyle \overrightarrow{AB} as a simplified expression in terms of i\displaystyle \mathbf{i} and j\displaystyle \mathbf{j}.
(2)
(b) Find a unit vector that is parallel to AB→\displaystyle \overrightarrow{AB}.
(2)