Question

Find the angle between the given vectors to the nearest tenth of a degree.

u = <6, -1>, v = <7, -4>

Answer 1

\[u\cdot v=\|u\|\|v\|\cos\theta\]
Find the dot product and norms, then solve for the angle.

Answer 2

So -34costheta @SithsAndGiggles

Answer 3

@amistre64

Answer 4

\[\langle6,-1\rangle\cdot\langle7,-4\rangle=6\times7+(-1)\times(-4)=42+4=46\]
\[\|\langle6,-1\rangle\|=\sqrt{6^2+(-1)^2}=\sqrt{37}\]
\[\|\langle7,-4\rangle\|=\sqrt{7^2+(-4)^2}=\sqrt{65}\]
\[\cos\theta=\frac{46}{\sqrt{37}\sqrt{65}}~~\implies~~\theta=\text{you can compute}\]

Answer 5

.917 @si

Answer 6

@SithsAndGiggles

Answer 7

@mathstudent55