Answer:
[tex]\theta=119.8138^{\circ}[/tex]
Explanation:
Given:
a)
From the vector addition rule we know:
[tex]R^2={A^2+B^2+2A.B\cos\theta}[/tex]
where
[tex]\theta=[/tex] angle between the two vectors with their tail at common point.
b)
Putting respective values:
[tex]7.6^2=7.1^2+5^2+7.1\times 5\times \cos \theta[/tex]
[tex]\theta=119.8138^{\circ}[/tex]