## anonymous 3 years ago Find the angle between the given vectors to the nearest tenth of a degree. u = <8, 7>, v = <9, 7>

1. anonymous

You could use the formula:$\cos \theta=\frac{ \vec u \cdot \vec v}{ |\vec u||\vec v| }$assuming you are familiar with the dot product of vectors.

2. anonymous

here it is on mathematica.

3. anonymous

that wouldnt let me open it @Sshmoo

4. anonymous

im just learning it so im still so comfused

5. anonymous

i'll try converting it to a different file, all it is is a graph of the vectors and a dot product. It just looks shinier.

6. anonymous

ohok

7. anonymous

here it is in PDF

8. anonymous

okk hm so

9. anonymous

so which of these would the answer be ? -8.3° 1.7° 3.3° 13.3°

10. anonymous

If you calculate cos theta, you get: $\cos \theta=\frac{ 8 \cdot 9 + 7 \cdot 7 }{ \sqrt{8^2+7^2}\sqrt{9^2+7^2} }=\frac{ 72+49 }{\sqrt{113}\sqrt{130} }=\frac{ 121 }{ \sqrt{113} \sqrt{130}}\approx 0.99833$Now take the inverse cosine (cos^-1 on your calculator) to see the answer.

11. anonymous

THANK YOU!

12. anonymous

yw!