Question

3. Find the angle between the given vectors to the nearest tenth of a degree.
u = <8,7>, V = <9,7>

a) -8.3
b) 1.7
c) 3.3
d) 13.3

Answer 1

Answer:

Step-by-step explanation:

$u.v=|u||v| cos \theta\\(8)(9)+(7)(7)=\sqrt{8^2+7^2 } \sqrt{9^2+7^2} cos \theta\\72+49=\sqrt{64+49} \sqrt{81+49}~ cos ~\theta\\121=\sqrt{113} \sqrt{130} ~cos~\theta\\cos~\theta=\frac{121}{\sqrt{113} \sqrt{130} } \\\theta=cos^{-1} (\frac{121}{\sqrt{113}\sqrt{130} } )\approx 3.3^\circ$