What Delta V was required?

[starchaser2020]

A satellite changes its orbit inclined 66° at 260.0 km altitude to a polar orbit at the same altitude. What Delta V was required?

... I am stuck.

do I figure it out using:

DeltaV1 = |V_transfer at orbit 1 - V_orbit 1|
and
DeltaV2 = |V_transfer at orbit 2 - V_orbit 2|

or is there another way?

Thank you in advance!

 

[haruspex]

|V_transfer at orbit 1 - V_orbit 1|

I'm not sure what two velocities those variables represent. One that thing that may be confusing is that while in an orbit there is no single velocity that goes with it - the velocity keeps changing.
Think of it this way: in order to switch from one orbit to the other, you have to get to a point on the target orbit. How is that going to happen? Will it require a deliberate velocity change? When that has happened, what velocity change is needed to complete the process?