FEN = 8/1R1Q4/r1p5/k7/2KP4/8/8/8 w - - 0 1
Well, I'm curious what the solution is because everything I can come up with only works with black playing imperfect. Closest I can get is rook to b4. Black only has one move to prevent an instant checkmate. Rook to a8.
It has a "forced" mate in 2. So it's not that the puzzle is solvable if black plays sub-optimally. You may try your approach on the interactive board link shared in the post. It will let you try moves without giving hints so that you can learn from your mistakes. If you're stuck then click on "Analyse" button which can help you see different variations of the puzzle. Hope that helps :)
I am really bad at notation, or English names of pieces.
Spoiler
Something lesser piece b5 check, pawn takes b5, queen takes pawn b5 check-mate?
No, king would move down instead of pawn taking.
Sooo...
First
then Black has two options:
Option 1
c5 2. Qb5#
or
Option 2
Kb4 2. Qc7#
That took me longer than I care to admit.
Doh, of course... I was never very good at chess and it's been ages since I played... Time to think anew...
I guess you can simply play on the interactive board and it generates the PGN formatted moves below which can be useful to learn the notions :)
Thank you, I didn't know the link led to an interactive board.
Let's enjoy chess puzzles in this community !