Question

find a*b (dot product)
if |a|=6 and |b|=5, the angle between a and b is 2pi/3

Answer 1

\[a.b = |a| * |b| * \cos \theta \]

Answer 2

\[\cos 2pie/3 = \cos 120 = \cos( 180 - 60) = -\cos 60 = \frac{ -1 }{ 2 }\]

Answer 3

k then is 6+5*-1/2

Answer 4

6 * 5 * -1/2

Answer 5

k

Answer 6

-15

Answer 7

Yup

Answer 8

k thank

Answer 9

Welcome