Velocity Addition for Orthogonal Boosts in SR

[tfhub]

Hi,
is there any general formula to find out the final velocity w, happened by a boost in x direction forst and then to y direction?
I could find the boost matrices for both and I know it's not purely another boost, rather a boost and a rotation, but I am really confused which formula to use to find w.
does the relativistic velocity addition formula apply here ? (u+v)/(1+uv/c^2)?

 

[Orodruin]

No, it does not apply. It does not even have the correct low velocity limit.

There are some different ways of doing this, depending on your level of understanding. How much SR are you familiar with?