#does anybody know a formula for this?
14 messages · Page 1 of 1 (latest)
hey I'm not sure how to do question c
I know if you want to find an angle of two vectors you use this formula
$\frac{\mathbf{u} \cdot \mathbf{v}}{|\mathbf{u}| |\mathbf{v}|}$
Toby
but im not sure how to do it for a vertex
the solution is arccos(√2/3)
would really appreciate any help
the question asks you to find the angle at the vertex A.
which is the angle between the vectors AB and AD
you can find AB with OB - OA
and AD with OD - OA
all of which are given to you in the question.
now that you have AB and AD vectors, you can use the dot product on these 2 vectors.