Forces A and B has a resultant force C with magnitude of 200N.
The magnitudes of A and B have the relation of 2||A||=3||B||.
$\theta$ is the angle between A and C, and the angle between B and C is 2$\theta$.
Determine the value of $\cos\theta$ and $\cos2\theta$.
Then find ||A|| and ||B||.
General tips to get me started on this is appreciated.