Rook and bishop/knight against rook

Is it possible to force a win? For RBK vs RK I've always been told it depended on the position, but no further information could be given, I've looked a bit and found nothing on the net. As for RNK vs RK, my guess is that it wins, but I'm not so sure, anyone has information on that?

I think I've seen positions like that in endgame books. You'll probably have to get yourself a good endgame book for details on this sort of thing.

--Fromper 

R+B vs R is usually a win unless your opponent has studied the second-rank defense.

R+N vs R is usually a draw.

I just pulled up some statistics, at the 1500-2100 level R+B vs R is won roughly 50% of the time while R+N vs R is won roughly 25% of the time.

both are drawn with best play; R+N vs R is drawn pretty eaisily, (atleast for a 2100 lichess.) and R+B vs R is still pretty easy, though there are some dangers.

i once stumbled into a R and B vs R with 50 seconds on the clock as the defending side, my opponent had over 30 minutes. i self discovered the Szen position and held the draw. But i woudnt call it easy you have to be alert.
R vs K is not hard. The knight simply doesnt let the king get to the right position to deliver the checkmate threat and wiggles out.
as a bonus R vs B isnt hard either just put your king on the square color corner opposite to the bishop you have.

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