Answer:
The vector that describes their hike from their starting position to their final destination is [tex]\vec r = 7\,\hat{i}+1\,\hat{j}\,\,\,[mi][/tex].
Step-by-step explanation:
In this problem we assume that orthogonal axes coincide with the north and east. We proceed to translate each sentence from statement into vectorial equations:
(i) A group of hikers walks 3 miles east and then 1 mile north:
[tex]\vec r_{A} = 3\,\hat{i}+1\,\hat{j}\,\,\,[mi][/tex]
(ii) After taking a break, they then hike 4 miles east to their final destination:
[tex]\vec r_{B} = 4\,\hat{i}\,\,\,[mi][/tex]
The vector that describes their hike from their starting position to their final destination is the sum of the vectors deducted above. That is:
[tex]\vec r = \vec r_{A}+\vec r_{B}[/tex] (1)
[tex]\vec r = (3\,\hat{i}+1\,\hat{j})+4\,\hat{i}\,\,\,[mi][/tex]
[tex]\vec r = 7\,\hat{i}+1\,\hat{j}\,\,\,[mi][/tex]
The vector that describes their hike from their starting position to their final destination is [tex]\vec r = 7\,\hat{i}+1\,\hat{j}\,\,\,[mi][/tex].
