Question

51-8; and v=

V5i+j. Round to the nearest tenth of a degree.
Find the angle between u=
65.90
c.
a.
90.40
33.30
b. 98.50
d.
Please select the best answer from the choices provided

Answer 1

b. 98.5°

Explanation:

There are a number of ways to do this. Perhaps one of the simplest is to compute the angle associated with each vector, and find the difference.

We can compute that angle as ...

vector angle = arctan((coefficient of j)/(coefficient of i))

where the arctangent is computed in the appropriate quadrant according to the signs of i and j.

∠u = arctan(-8/√5) ≈ -74.38°

∠v = arctan(1/√5) ≈ 24.09°

The angle between these vectors is then ...

24.09° -(-74.38°) = 98.47° ≈ 98.5°