Question

Fin the angle between u=<2sqrt(2), -4> and v= <-sqrt(2), 1>

Answer 1

\[cos(\theta)=\frac{u\cdot v}{|u||v|}\]

Answer 2

so we need these numbers.
\[u\cdot v=2\sqrt{2}\times -\sqrt{2}+(-4)\times 1=-8\]

Answer 3

if my arithmetic is correct, please check it

Answer 4

\[|u|=\sqrt{(2\sqrt{2})^2+4^2}=\sqrt{24}\]

Answer 5

\[|v|=\sqrt{(\sqrt{2})^2+1^2}=\sqrt{5}\] and so
\[|u||v|=\sqrt{120}=2\sqrt{30}\]\]

Answer 6

\[\cos(\theta)=\frac{-4}{\sqrt{30}}\]

Answer 7

i get
\[\theta = 136.9\] in degrees, but you should check my arithmetic i make misakes

Answer 8

alright, thanks man

Answer 9

yw, but please check, especially if you have to hand this in